A lot of folks use a red bulb heat lamp for heat. Tractor supply or similar has them and they aren't real expensive. I prefer a heat plate style warmer personally. Less risk of fire and more natural for the birds but a bit more money. We use the larger version of this unit:
https://www.chewy.com/brinsea-ecoglow-safety-600-chick/dp/221003
It says it will handle 20 chicks but 10-15 is more reasonable for larger fowl that grow quickly. The larger version can handle more. We have no complaints with the brinsea but there are other brands as well.
If you go with a lamp instead, be sure to get a brooder thermometer and use it.
Other than that, you mainly need bedding with appropriate feeders and waterers. Chicks do well with the long narrow feeders with guards over top or small gravity feeders. Most waterers are gravity style but must be small enough that they can't drown in them. Plenty of options. We like these because they can be used for both food and water:
https://www.chewy.com/lixit-chick-feeder-fountain-32-oz/dp/264622
I also use them as supplemental waterers for the flock when it's hot or we don't have chicks. The adult birds being able to still use them is nice.
I use puppy pee pads for the "bedding" for the first week or so, changing them daily. Once they know what food is and everybody is moving around well, we switch to shavings.
I always recommend keeping some sav-a-chick or nutridrench around, especially if you have chicks shipped. Sometimes the supplements really perk up struggling chicks. Not really a brooder supply but a raising chicks supply, I guess.
https://www.amazon.com/dp/B07B53BHLW/ref=cm_sw_r_cp_apa_i_kKR-FbT768NA6?_encoding=UTF8&psc=1
You won't need that much for 1 group of chicks. That said, it can be given to adult birds too. We give electrolytes regularly when its real hot.
You can make or get perches for them to practice roosting as well.
Couldn't tell if you have one in mind but the brooder box itself can be just about anything, from a large box to a plastic tote to a corner of a coop wired off (if temperature allows). Just remember that you'll have to have it covered after a couple weeks so they don't escape. I have a window screen that gets laid over ours once they're little flight risks. We use a large black feed bin for small groups and I built a large wooden brooder for when more space is needed.
That's about all I can think of outside of a quality starter feed, chick grit for once they start eating anything beyond feed, etc.
The links I used are for Chewy.com. Amazon also has a good selection. Here, tractor supply and rural king carry some supplies as well.
I hope this helps. Brooding can sound complicated but its really not bad once you get rolling with a routine.