Amateur Radio (Ham) will always be the best choice for reliable communications. Even at the technician level, an amateur radio license can access UHF, VHF, and HF frequencies and transmit with enough power to reach half way around the world (10m SSB) or more importantly to communicate through one of the hundreds if thousands of repeaters found across the US (2m and 70cm).
What everybody else always says when this question comes up. Ham is the way to go. For a couple of reasons.
ham frequencies have a lot more ability to cover distance.
getting your ham license requires learning a lot more about radio frequencies and communications in general. I’ve put this off for a long time but now that I’m studying for my ham, I’m realizing how useful this knowledge is. Radio communications are not simple. There are a lot of variables. It’s helpful to actually understand them a little bit.
my cb radio with a 48” antenna on my vehicle barely communicates with other vehicles on the interstate, when I can see them. My handheld baofeng ham radio can pick up transmissions from a repeater station 4 miles from my house, while I’m sitting inside my house. In a wooded, urban city. There is no comparison between ham and other, less powerful frequencies.
The real question is what are your intentions for said radio. If your only talking within sight on trails with other vehicles gmrs and that particular radio will work just fine. If you are looking to go more than a few miles gmrs or cb is probably not your best option as others have mentioned HAM and a cheap handheld baofeng radio is your best bet.
With a little investment CB is just fine for talking across town with your buddies but hardly reliable without serious equipment with further ranges than a few miles.
And this is how it all begins! Consider something like a TYT 9800.
I have a 7800 in my truck with a mag mount antenna that I pop on the roof, running the coax out the window, and have good reception into and out of repeaters 20 miles away. Terrain matters of course. Up high you can hear and be heard a long ways. Deep in a narrow valley, maybe not. That’s where the cheap 8w handheld backup comes in.
Then there is the Yaesu 891 for when I think I might have to get in touch with someone half way across the country to call for help
On the transmit side there is not a lot of difference in most of the radios from a lowly $29 Baofeng to a $350 Kenwood dual band radio, as all radios have to meet the FCC emission requirements for transmit. Some have better TX audio and some not so good but the antenna system REALLY makes a big difference. Having even a small external mag mount antenna on the outside of your vehicle adds miles to your range even at 5 watts. Where I find a big difference is in the quality of the receivers - the Japanese radios (Kenwood, Icom, Yaesu) almost always have more selective receivers with better filtration and better audio quality then the Chinese radios (Baofeng, Waxun et all) will ever have - but at 2-5 times the price. The good news is most of the electrical noise issues that swamp the little Chinese radios is all but absent in the woods so buy the best radio you can afford and enjoy. When it comes to mobile radios a little bit of extra money can buy you higher power, more features, and a more user friendly radio that does not come with a manual written in chinglish that nobody can understand, but even with the low dollar radios a good antenna system will get you a long ways. In the 20+ years I've been working on VHF, UHf, 700/800 MHz stuff I've seldom found the brand of the radio makes a huge difference in anything but name bran recognition and sometimes how resilient it is to the beating law enforcement folks dish out.
For trail comms GMRS is great, however you might look at getting one of the mobile units. Transmitting on a handheld from inside the vehicle may result in less than stellar performance.
For emergency comms, as mentioned ham radio takes the cake as far as radio is concerned. If you are really out in BFE alone and have a legitimate concern for safety a PLB device may be a wise investment.
Ham radio isn't just about voice communications, you can use it to track your vehicle (and others) and possibly send a SMS text message to someone's cell phone even if you don't have a cell signal. Though it's a good tool to have in your bag of tricks it helps to stay proficient at it (as with most anything) so it helps to have a license and to be somewhat involved (chat to other hams on your drive to/from work, check into weekly nets, practice manually entering frequencies, etc). Some radios have more of a learning curve than others and if you just toss a radio into your "go bag" and think I will pull it out and use it when SHTF, you are likely to fumble with it and maybe get it half assed working....maybe.
What ham radio should you get? That's up to you, most anything from the big 3 (Kenwood, Icom, Yaesu) would work fine, TYT would be ok, Midland has a ham radio on the market for a great price, maybe BaofengTech. It depends on what options you want/need and what kind of budget you are working with.
Your antenna should be as high on the vehicle as you can live with because in VHF/UHF antenna height is king. Example: A buddy and I were convoying down the highway, I had a 1/2 wave antenna on my fender, he had a 5/8 wave antenna on his roof. He was able to talk to another buddy 30+/- miles away who was also running a 5/8 wave antenna on his roof. I was not able to even hear him. I have another Jeep with an antenna on the roof and I could tell the difference hearing and getting into a distant repeater. With the roof mounted antenna I was on the fringe of the repeaters coverage area, I could hear and get into the repeater most of the time with some scratchiness. With the fender mounted antenna I could neither hear or get into the repeater.
In my research to find a handheld, it seems the Yaesu FT-60R strikes a good balance on quality and price and capabilities. Also highly rated on Amazon and eham: https://www.eham.net/reviews/products/49
"I need just trail but its bothering me a little in case emergency if I will be able to get someone attention"
If you are a person who goes out in the backcountry by yourself, you might want to invest in a Garmin inReach Explorer. It has satellite capabilities and can be used to text your location to friends and family while exploring as well as the ability to directly contact SAR in the event of a life or death emergency. I use this when out in the desert because you can't always rely on hitting a repeater or someone actively listening on the other end.
Ham is great in the case of a civil emergency. Last night after the earth quake in Ridgecrest my mobil ham had a lot of activity, and it would have been really simple to coordinate with others.