No problemo dude! I had a blast. If you want to work from B&W to color I'd recommend this old video from Dave Rapoza:
https://www.youtube.com/watch?v=CavSMH32-is^His methods in the video are super basic but it's a good way to start. I also highly recommend his orc tutorial on gumroad if you have a couple of $.
For a more procedural approach you can try this:
https://www.youtube.com/watch?v=JtDlmLYvWjE^Works for mobile-game style art.
If you want to learn gradient maps you can try this:
https://www.youtube.com/watch?v=OvSwG3M-9Lo^Don't get too reliant on these though...
If you want to learn some color teory and other stuff you should check out Marco Bucci's channel:
https://www.youtube.com/user/marcobucci/videos^I don't like his art but he's a great teacher.
Here's my 2 cents:
1. If you want to go from grayscale to color do it slowly. Do a light washes on your image with adjustment layers like overlay, multiply, color, and soft light. Just play around with them but don't approach it as "one step" where you're like "He's green and I'm done!". Don't do it at the end either. Bring in the colors when you're ~30% into your image and paint over that shit or it'll look really bad.
2. Remember that colors have their own values. If you try making a dark gray tone into yellow it will not work. You also can't get a saturated red from a light value. Experiment with this and you'll see what I mean. This is another reason to use adjustment layers like multiply and overlay to do some of your color work.
3. Try working in color from the start every now and then and do a lot of studies from photos and other artists. You'll get much more vibrant results if you have the skill to start your image with color.
