You need no license to drive a farm tractor as long as you do not drive it on public roads.
no
Generally in any part of the world where you need a license to drive a car on a public road you will need a license to drive a tractor on the road. It will vary between country to country, even state to state wether you need a special license class or wether the tractor falls under an existing (generally mass based) category.
you don't need a special license to drive an RV just a regular drivers license
You just need a regular drivers license to drive an RV Class A in Virginia.
A standard driver's license- usually called an operator's license.
Although it may not be true in all countries, in North America you may operate a tractor with just a driver's license if done for a farm. You will likely need a special license for any other use.
To drive a semi truck, you need a specific driving license that allows you to drive that class of vehicle. As well, as proper education and training such as driver's ed.
I believe that a Ford F650 requires a class B license to drive.
The same license as you need to drive anywhere else.
You do not need a license to drive any kind of boat.
If you intend to drive the tractor on the "public" roads, then yes you will need to take the DVLA "tractor or specialist vehicle" test. If you NEVER go on a public road or highway (even briefly) you do not need to take the test. - the penalties are high if you are caught without a license driving a tractor on a public road. So it's best to take the test, even if you don't think you will need it. It's only £62 during the week, so a small amount.
It's a private farm. As long as you don't get near the public, you don't need a license.