If i can afford my own semi truck would i need a cdl to drive it?

Yes, you would. It would not matter if you were not driving it for commercial purposes, it is classed as a commercial vehicle, so you must have the appropriate license.

Yes

Not if youre only driving it on your own land.. If you're going on a public road then yeah

Yes,most definitely. If you live in the United States.

Of course.

Yes for sure.

Farm tag

Yup

Why would you think that owning your own truck would have anything to do with it's legal operation on the highway? Insurance companies don't give a shit if you own your own truck, you lease it or you work as a company driver.

If you intend to earn money with the truck, you will need the appropriate license that will allow you to work commercially. That applies to ALL aspects of the Transportation Industry... ships, airplanes, railways.

What's a cdl?