Where to begin ?View other answers to this thread
I think it's probably a good idea, when exploring a new tool, to follow a brief introduction.
This can be in whatever format you like - book, blog posts, video, ask a friend. Probably many tutorials out there are better than what fits in a typical answer.
Once you have a general idea, you can look around. Possibly try to achieve some small change, so you have a goal. You can then ask/look up things you're not sure about, but it's hard to formulate specific questions if you don't have a general idea about the tool yet.