I was wondering how hard it would be to replace a head gasket on my friends
Sportage? What all would I have to do to do this?

What size engine? SOHC or DOHC?

If you aren't comfortable with the basics involved in replacing a head
gasket, then this isn't the job to start into without live help and
guidance.

Also be forewarned that if the cylinder head gasket is leaking due to
overheating or the vehicle won't start because of a head gasket leaking
compression, it's most likely that a cylinder head will be needed.

I do have the basic knowledge of how to do it. However I havn't worked on a
Kia. I was just wondering how much work I would have to put into it. And
all my friend told me about the engine is that its a DOHC

I think the 2.0 DOHC has a rather annoying E.G.R. pipe. I know it did in
1997 but that the EGR went away for 1998 and newer. I'm not sure about
1995, there aren't many older than 1997 around here.

I'm working on my '95 Kia Sportage Ex(DOHC) to inspect and replace the head
gasket. Thermostat was acting up and I'm sure I blew the gasket and was
down to 3 cylinders, burning radiator fluid.
Drained oil and radiator, and then also main engine feed on the bottom
driver's side from the radiator. The remnants of what was in the engine
showed me some oil in the radiator fluid, which I was told by a friend
that this is most likely the issue. Now I have to pull everything off to
check the head gasket.

If the E.G.R. pipe is the big metal pipe mounted above the engine, which
goes from the air intake and sensor assembly on the driver's side over to
the intake manifold assembly, then yes, this is the case. However, would
rather do this myself than pay someone $1600 to do it...San Jose, CA
prices, no doubt.