Welcome to the forum and soooo glad you asked instead of a post saying help, my ray is about to die.
Get started on something simple and learn the nitrogen cycle as well as you can.
You need to know the importance of:
Water changes
Not cleaning out filters in tap water
not overfeeding
Cycling the tank
Stability
Ask as many questions as possible and buy a good test kit for ammonia, ph, nitrite and nitrate, dip strips are ok for weekly testing but not very accurate.
Good Luck