Howard: I've replaced screens -- it's very easy.
Here's a tutorial:
It really is not hard once you have done it once yourself. The biggest trick is to make sure you get the screens tight when you replace them. You can find everything you will need at your local home improvement center and probably even Walmart.
Perhaps you might wish to considered the screen tight system?
We had ours installed in 2015 -with remodel and addition- to our surprise it’s a wonderful system.
It consists of the regular fiberglass mesh screening stuffed into an edge frame sealed with rope like stretchy spline and has a plastic snaps on Tupperware type sealing strip to cover your raw edge.
We just repaired a huge panel after a dog excitement accident. It was pretty easy to work with. We just bought replacement screen + tub of the spline and a hand spline tool and the job was completed without much effort. I would say its diy friendly....at least the repair was. It was far easier than a more old-school staple screen and cover with it with wood —system that we had a prior residence.
I hope this helps!