The Western Australian Museum has put out a free coral identification guide. There are other such guides out there but I have found most of them don’t have photos of good enough quality to really assist in making an identification. This guide is an exception. It won’t cover 100% of the corals you might come across but I think it does a pretty good job with the major ones you are going to run into.
Here is an example of part of a page. As you can see it has a nice array of photos and brief description. This is an identification guide so it isn’t going to help you take care of the coral, just know what it is. You can then turn to the Internet, forums, etc. to learn from others the best way to help it thrive.
Though you can download it from their web site (https://museum.wa.gov.au/kimberley/publications) I have included it here for you. It is free to use and share so feel free to pass it along as I have done.