As some have stated before ask yourself
1) What do you want from it? Are you just looking to practice, possibly hunt small game, shoot extremely accurate long distances, plink like a mad man.
2) What are you willing to spend? I would suggest inexpensive (probably bolt) at first as many great .22 can be had for cheap new and used.
My thoughts through trial of friends and my own and are only my opions (though if you ask me they are the best thoughts

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Bolt Actions
1) Cooey Model 60: Inexpensive used rifle, I've never had an issue, and have found them fun an accurate. I do prefer a detachable magazine as I can load up several and swap them out.
2) Savage Mkii: Again another inexpensive .22 that has been great fun for me. The accutrigger is a nice touch to make a bad trigger better. The detachable magazine does stick out which some find annoying. Big bonus is it can be found with iron sights, seems rare among new rifle
Semi Auto. A big thing for myself in semi auto is the availability of larger magazines. No, 25 - 100 rounds isn't required, yes it can be a pain to load, but it is FUN!!! to shoot.
1) Ruger 10/22: There Is a reason the 10/22 is so popular and has so many variants and aftermarket parts. It was previously my #1 recommendation, but with controversy over the legality of 10/22 Magazine over 10 round
2) Remington 597: With Remington bankrupt at the moment new material could be hard to come by. My experiance is that the larger magazines can have feed issue at time, but it is still a fun. Not a terrible choice, but better options do exist.
3) Savage A22: I have a love hate relationship with the Savage A22. Removing ALL the factory grease and giving it a thorough clean and re-oil has made me love it, but prior I hated it as I had to many failures to eject to the point it ruined any fun. After the clean I mentioned I haven’t had any subsequent issue with any ammo and is a pleasure to shoot. I would recommend it cautiously, as my experience (sample size of 1) is that it is fun when you get it working, but a pour initial experience is not worth it. I have several other minor pro’s/cons that your welcome to pm me about if you want to hear me rant.
4) GSG-15: Limited experience but it was nice to use and handle. The owner (a friend) claimed it has been quite reliable, but the thought of stripping it down is apparently a bit daunting, to him at least. I'd probably go a gsg-16 as I want option of the drum mag. (Just saw a drumag for gsg-15)
5) Savage 64 FX: Skip. Again a limited sample size, but my experience has been meh, to picky on cheap ammo