I have a small oil leak on my 4cyl 98 s-10 pickup. Not huge but would like to fix it myself if I can. Drips down on the exhaust pipe. If it's the valve cover, how bad is it to change

Valve cover is a pain on 4 cylinder.
I would rather change 2 on a V6 than one 4 cyl.
But you need to find out for sure where the leak is.
Craw under there and have a look and see where the drip is coming from.
They make a leak dye kit for the hard to find oil leaks.
MT