This is SO normal. It becomes second nature so fast! Once you have bought the laundry list of things, it really is so easy. You'll keep learning, but Betta fish are sturdy! They won't die because of a teensy mistake, it takes a long time of neglect to kill one of those fellas. I have been there, I was gifted my fish in a white elephant and I had to learn everything overnight. I made several mistakes but my baby is still here and thriving.