Can I restore an older iPhone backup?

I just got a new computer. I copied every file over I had, including all the user info and all the files in there like appdata and the mobilesync in the Apple folder. I see about a dozen backup folders in there.

After I installed iTunes on this new computer, I just did my first backup, which is in that folder on C: (the others are on another drive).

1) Can I copy them over and have access to them?

2) Is that safe to do?

3) Will I be able to restore an older backup over my current 16.5 version? (There was an app on there that I deleted, and I can only access some info from within the installed app in that backup. So I was hoping, if I restored it, and accessed my data, then I could restore back to the current 16.5 I'm running now).

I just need to get access to that data from within the installed app. Reinstalling it will not give me access to what is (was) in there in that backup.

If this makes sense.

Thanks!

Don