Well, simple is a relative term

I have friends
that couldn't be trusted to remove the oil drain plug
from their car.
It took me the better part of 2 weekends the first time.
It will take me the better part of a day the second time
and I'm not a slouch around tools. I did do the water
pump, thermostat, the tensioner, all the oil seals, the
oil pump leak fix, the plugs and the belts. All things
you'll want to change as well
If you are good with tools and your hands and can follow
the service manual exactly, you can do it.
If you've never worked on a car, take it in.
The downside is that you can totally ruin the
engine if you get it wrong. The upside is that
you can do it for about 1/3 the cost and learn
a alot about your car.