Hi! welcome! Food, water, shelter! Those are your basics.
Food: do you want organic, non gmo, corn free, soy free? Whole grain, pellets, or crumble? Fermented? Are you going to sprout seed as extra nourishment? Meal worm farm for extra protien treats? Those are some of the more in depth questions to ask yourself.
Water: how will you heat your water in the winter so it doesn't freeze.. I actually never thought of this at the beginning of the year and im now stuck trying you figure it out last minute instead of being prepared.
Shelter: how many birds will you have? Will they free range or be in a run? Taking that into consideration will determine how big your coop and run should be. No less than 3 sq ft/bird and honestly, the more room you have the happier your hens will be. Mud management in the run during the wet seasons. Also need to look into predator proofing! What predators do you have in your area and how will you keep your flock safe from them. Also, will you be using heat/ light in the winter.. this is a huge one to look into and research to make your best educated decision for your flock.
A few extras to consider when choosing a flock.. are you wanting a diverse colorful egg supply? Do you just want high production? Do you want a friendly flock you can mingle with? Just a few things to think about when you pick your breed(s). Hope that helps!