>>1901572you shouldn't need to adjust your limit screws at all, if it used to work, ie, it was setup up correctly once upon a time. They don't tend to drift and don't need adjustment.
A skipping chain is either due to shifting, or worn cogs/chain. You want to identify which kind of skipping it is.
If it's shifting, the most common cause is the indexing is out, so you can just twiddle the barrell adjuster to fix it, if you get it in your head what in or out does. Next would be if the derailer hanger is bend, which you can identify visually. Next would be cable housing with excessive friction, which is cheap to replace.
If your drivetrain is -slipping-, not skipping then the chain is probably extremely badly stretched and the chain and cassette and maybe chainrings and jockey wheels needs replacing.
I suggest you consult RJ the bike guy on youtube and Sheldon Browns articles on setting up derailers.
