Welcome back to the hobby and welcome to the Herd, Yorkie!
As far as painting goes, I'd keep it simple to start. I do recommend using spray cans to start. You'll get better results than hand-brushing, and learning to spray is good practice for such time as you might invest in an airbrush. That's what I did, I practiced using a light touch with rattlecans-learning to apply the paint lightly, learning masking with tape, etc.
I recommend using a primer as a first coat, and then applying your finish colors. I use Tamiya products, mostly, but there are others. Tamiya's Fine Surface Primer is an excellent product. It covers well, doesn't obscure fine details (unless you lay it on too thick, but like I said, you can practice the touch), and Tamiya has a series of aircraft colors in rattlecans, too. If you have a hobby shop near you, chances are they carry Tamiya's products, but you can also find them online, from TamiyaUSA's site or other online vendors.
Remember what the New Yorker told the tourist who asked how to get to Carnegie Hall: "Practice, practice, practice." The more you build, the better you'll get. But remember, too, that it's a hobby, and you should enjoy what you're doing.
I look forward to seeing your Spitfire!
Best regards,
Brad