Win the lottery!
I keep a 65 gallon fish only with live rock aka FOWLR* along with a 40g tropical community. I recommend starting with a 40 to 75 gallon FOWLR tank for a beginner. This size is easier to maintain water parameters**, too small and even a slight change can crash a tank. A hang on back filter can be sufficient but you have less maintenance and longer intervals between cleanings with a canister filter, this and a good led light will get you started but you will eventually end up getting a protein skimmer and a wave pump or 2. I wont discuss sumps and refugiums here. If you want a true reef setup, the equipment list gets even longer. The biggest recommendation I can give you is to be very patient and do not rush things. You need to research what makes a "cycled" tank and a "matured" tank. I wish I had more time right now to go further into detail both those trees aren't going to cut them selves. Im here if you wish to discuss more.
* FOWLER- can include inverts such as anemones, fan worms, shrimp and crabs. this is usually used to describe tanks that house no corals .
** Water parameters- include PH, ammonia, nitrates and nitrites, salinity and hardness. in the beginning these will need to be watched on a daily basis. once you gain experience and know your tank you can drop back to a once a week check unless you notice something that prompts you to do otherwise.