You will need a tank of preferably at leats 2gallons+ for a single male betta, females need slightly larger. If you don't cycle the tank you will have to do once or twice weekly 100% water changes with dechlorinator, if you want to do smaller water changes you will have to get a filter and cycle the tank. The tank will need a heater but lighting is optional, you only need it if you have live plants, if you go for fake ones get silk plants instead of plastic ones as the plastic ones can tear the bettas long fancy fins.
ps: you should realy post this sort of stuff in the betta section.