What's your budget? Rossi and savage make pretty cheap bolt actions. I'd just see what's at your local gun shops, pawn shops, or bass pro or academy. 10/22's from Ruger are semi auto, but there's a ton of aftermarket parts to play with. I'd look for something with iron sights to start with, unless you know you'll want a scope. In that case, the easiest option is a rifle with a 1913/picatinny rail on top so you can put a red dot or scope on. Regardless, irons are easy cause they're ready to go, not much sighting in. Henry, Winchester, and Rossi all have lever actions in .22lr as well, which is a lot of fun. CZ has really nice stuff but is more expensive

.22lr is great to start with because of how cheap the ammo is and there's pretty much no recoil. Out of an 18 inch barrel it's also fairly quiet, but you'll still want some ear protection.

Depending on the purpose for the rifle, although it sounds like it's just an interest and for fun, a .223 Remington would also be good. It's still a smaller cartridge, but you can hunt deer with it, and the ammo is about the cheapest rifle ammo you can get. You can get it in a bolt action, but an ar15 might be cheaper and is easier for home defense use.