I agree with Styna. Look into adopting a turtle from Craigslist or an animal shelter, and make sure that its given proper care, and plenty of space. Owning a pet turtle can be a bit costly (I used to have two), so before you decide to take one in, make sure that you can handle caring for one
A lot of people have turtles as companion animals.
I would try looking on Craigslist or something like that, to see if anyone is trying to rehome one.
Don’t buy one from a store, and definitely don’t take one from the wild.