I'm not pro but...
Yes a glaze is to fill swirls before waxing instead of correcting the paint using a rotary/DA.
Pre wax cleaner is just a light polish to clean the paint work before waxing/sealing to get the best bond.
Some people prefer wax's some like sealants better. A lot of people use wax on warm coloured cars for a deeper/wetter look and sealants on light coloured cars as a sealant is more reflective. Personally I can't ever see what they mean
but I haven't really experimented yet to see.
Plastics can be coated in such products like gtechniq c4 etc
Once car is protected just snow foam if it's dirty if not I just rinse, wash using two bucket method and a mitt. Gtechniq microfiber mitt is great. Then rinse, dry and if you want use a QD depending on what you want. Then if like me dress the tyres, grills etc