I know you only solicited answers to your specific questions, but since you framed it in the context of a person returning to gun ownership with little experience, I will offer some unsolicited advice. I am sure more will follow and a lot of it will be good. I'll just get it started:
1. Besides the slide lube of your choice, you'll want a gun cleaner and tools. There is a variety of cleaners out there and while they all work, the ones best suited for your use may depend on the type of ammo and powder (propellant) used. Some ammo produces more carbon fouling and some produces more copper fouling and various solvents are better or worse for each. For tools, I suggest a short pistol cleaning rod. I like one-piece Dewey rods because they're inexpensive and I can buy one for each tool (patch holder, jag, brush, etc) and not have to change the tool tips. You can also use a "bore snake" which work quite well indeed except in the case of bore obstructions.
2. Find a holster that works for you and get it. Make sure your first holster is not a cross-draw or appendix carry simply for the sake of being accepted at training classes and on the firing line at the range.
3. Sign up for training. A day on the weekend for some local training is a good start. You will be well-advised to attend a multi-day training academy when you can. ITTS, Thunder Ranch, Sig Academy, Rogers, Gunsite... something like that. If you indicate what state you live in, you can get advice about where to go. It can costs hundreds to thousands and some people get hung up on that but it's ill-advised to be cheap about training. Your skill is critically important to your results in whatever endeavor you have. Don't put it off until you get better or deeper into it. Give yourself a good start.