Nothing wrong with the Radial Glider - bit behind the times but a good single handed sea trout/grilse rod even today. Bit heavy for the troots tho
To be honest not the best rod to learn on..... but then again why not:? It does the job and the principals are the same so yes, it'd be OK to learn with.
The Sigma is indeed a spinning rod
I canhear ardent spinners getting ready to shoot me but one spinning rod is much like another so it'll be fine to learn on
Flies - loads of places online you could look but might be more fun to just try a few and see how you get on......
Unless they're in mint condition you'll probably end up replacing them anyway
Good luck