Salutations from a complete novice. What's your recommendations to get started?

Note: A FLGS in town actually has a mini-painting workstation that you can use for $5/session, or as part of their monthly subscription for playing TTRPGs onsite. Since I play PF2E there several times a week I have that subscription. So I have a place to paint that's already kitted out with just about anything you could need for mini-painting. (I think they charge extra if you want to add stuff like grass, sand, etc. to the mini, but the primer, paints, sealers, etc. are all included.)

I have two awesome minis arriving soon that are unpainted, so I'm looking for online sites/videos that start from "I know nothing" and work up from there.

Thanks in advance for any and all guidance you can provide!

I'm wrapping up a project and I had an idea to mix matte with glossy elements. I've got a spray can of Testors Spray Dullcote and then was wanting to paint the glossy elements by hand with a different gloss coating/finish. How well would those interact with each other? I'd obviously let the matte finish dry first, but would the matte "cancel" out the glossy effect or does it have some other interactions that basically make it not worth pursuing?