Welcome to the forum! Your elephant ear (EE) marble betta is adorable!
Since you live near Petsmart, here are a few options for you:
Either glass or acrylic is OK. "Kits" are more expensive, but usually come with a hood/lid and a filter. Filters are optional for bettas as they breathe air, but it will help keep the water clean. If you use a filter, you'll need to adjust the flow so it doesn't push him around....
If you decide not to go with a kit, you can pick up a 3 gallon critter keeper (acrylic tank) with a lid for about $16, or a 5 gallon glass tank (probably without a lid) for about $15. You do need a lid or hood over the tank though, since bettas are really good jumpers!
No matter what type of tank you get, you'll need a heater (unless your house is around 80F year round). A lot of people recommend ones that have adjustable temperature controls. I use ones that are preset, and so far, I haven't had any issues with them - but I do see how having an adjustable one would be useful - if my guys get sick, I'd be able to raise/lower the temp (depending on what's wrong with them). The preset ones won't allow you to do that.
Water conditioner is a 'must have.' There are a lot of different types, but you need one removes chorine and chloramine, at a minimum. A lot of people here recommend Prime conditioner, which helps neutralize ammonia, too.... I use the Top Fin (Petsmart brand) conditioner which removes chlorine/chloramine - I do frequent water changes and test for ammonia, so I'm not worried about that building up in the tank. I also have API Stress Coat, which contains aloe and helps promote healing. (One of my guys bites his tail, and I don't want it to get infected.)
Pellets are the way to go. From what I've seen on this site, two brands are highly recommended: New Life Spectrum (NLS) and Omega One Betta Buffet. I wasn't able to get NLS at Petsmart, but my local store does carry Omega One, so I feed my guys this. There are a lot of different feeding 'strategies,' but basically, you should feed him about 4-6 pellets per day. Ideally, I try to give my guys 2-3 pellets, twice a day.
The marimo moss ball is perfect for his tank! Silk plants are good, as they're less likely to tear his fins. If you opt to use plastic, make sure they pass the 'panty hose' test: run the panty hose over them. If they snag, don't use them, as the sharp edges could just as easily snag your fish's fins. If you want to go with live plants, there are a lot of options. (I'll let the plant experts tackle those questions!)
The size of your tank, and whether or not you have a filter and/or live plants will affect how frequently you need to do water changes. It's important to keep up with these though, as you don't want ammonia building up in the tank. Check out OldFishLady's (OFL's) recommendations on water changes. The thread is stickied at the top of the forum.