to the forum. Introduce yourself in the newbie section.
I take it you have no fish right now and are looking for an easy-to-keep starter fish.
As long as you give a betta the proper care it will live for a long time.
There's probably a pinned article in the betta section if you check it out.
Basics, IMO:
Get at least a 1 gallon tank b/c they don't like it in bowls (I've experimented). This should have still or slow moving water, so you shouldn't get power filters, even if you could find one for such a tank. Therefore you should get an undergravel filter or a sponge filter for biological filtration and to keep the water quality stable.
Cleaning supplies, i.e. small siphon and/or turkey baster.
Food: hikari pellets and, preferably, some frozen food as an occassional treat and to vary the diet.
Some emergency meds: bettafix and some fungicide.
I think that's all. HTH