Welp some of the above posts could give you an indication.
This is not driving for fun. For OTR (over the road) drivers it's about pounding out as many miles per day as you possibly can. This is not sightseeing and after you've driven the interstate system a few times the scenery isn't all that thrilling. The best scenery is on the secondary roads anyhow.
This is about long hours, sleep deprivation and trying to keep 2 or more sets of log books balanced to show the nice Officer when you get stopped. If you are written up it ain't cheap. You can get deadlined for 8 hours or more depending on how many hours you drove in the last 24 or 60 hours. Once you get to your destination you have to deal with the truck and cargo both, then look for another load if they don't have one for you. You'll get home maybe once every couple weeks. You'll live in that cab, sleeping, eating and passing time (and gas

) there instead of being at home. This is not a 8 hour day, its 10+ hours of driving then other tasks thrown in, a few hours of rest (if you stay legal) then head out onto the road again.
The above is if you work for a company that provides the truck.
If you are an independent OO (owner operator) you are responsible for all of that plus finding ALL your loads, buying and maintaining a truck, tires, road service, paying for insurance, all your tickets and also all your taxes spread out across the country not to mention trying to maintain a positive cash flow based on miles driven, time to destination and fuel prices swinging up and down like a demented elevator. Figure a fully loaded truck will get about 4.5 to as much as 6 MPG depending on speed and location (mountains) and you'll be filling a 300 gallon tank. At over $3.00 a gallon that's about a grand a fill up and it comes out of your pocket. Figure you'll be filling up every 1200 or fewer miles or about every other day. Also figure on 800 to 1000 mile days to try and make enough miles to get a decent paycheck. Every city you drive through will slow your average speed down to the point you are making an average of only 45 MPH to 50 MPH. Eastern routes will be even slower due to more towns and cities to drive through. Every day down due to maintenance or breakdown will cost you about $1500.00 out of pocket plus the cost for repairs and towing or service call.
If you get into hauling hazardous materials you'll make decent money but the regs are killers to follow. There are many more ways to get arrested doing that kind of work than straight freight.
While the act of driving isn't physically hard labor the job is very physically demanding. I invite you to spend a few hours at a large truck stop restaurant and look at the drivers. Take a good look at them and see if they really seem happy. It is a hard life and pretty lonely too since they are not home very much at all. You can figure that there won't be a home life and a retirement situation will be all on your own.
Talk to RPM and a few others that did this for a living. I just inspected the rigs and enforced the regs and that gave me an idea that I didn't want to deal with anything like that after retirement.
I've got a big rig (look at the avatar) but I drive it for private usage and am not restricted to the commercial license and requirements. Since my RV is also only about 20k lbs. I get better mileage, up to 8.5, and drive only when and where I want to. This makes it a better than break even situation for me vs a medium duty (F450 / F550 / F650) kind of RV hauler. Besides I have better breaks.
Last thing, lot lizards are not top of the line folks here, you have to be scraping the bottom of the barrel to scrounge truckers in a truck stop. EEEWWWEEEE!!!!
