Welcome. You've received a lot of advice already. I'll try not to repeat!
Check out Henderson's chicken breeds chart. That will help you to choose your birds. If you want birds who will lay for a long time and not be as likely to succumb to reproductive issues, buy dual purpose birds, and avoid the hatchery sex links and production birds.
Get your coop built before you get your chicks. They double their size every week! And if you have your coop built with an electric outlet available, you can brood your chicks right in the coop with a Mama Heating Pad set up.
@Blooie has an article and thread dedicated to heating pad brooding which is MUCH safer and more natural than using a heat lamp.
Make your coop and run big enough. Minimum recommendation is 4 s.f. in coop and 10 s.f. in run per bird. make your coop predator proof. This means 1/2" hardware cloth covering all openings. Make it well ventilated: minimum recommendation is 1 s.f. per bird, or equal to 10% of the open floor space. Vents must be above perch height, and perches must be above nest height. Perches also must be at least 12" above back wall, minimum of 10 inches per bird, at least 18" below ceiling, and have plenty of room in front of them for the birds to fly down from them. Nest boxes: at least 12' x 12' x 12' with a 4" lip and a landing perch in front of them if they are not floor level, and one per 4 birds. Bedding: plan on the coop being deep enough for at least 4" of bedding on the floor. Something to think about if you do consider buying a pre fab. I've been assessing prefab coops for years, and have not yet seen one that is adequate to meet the needs of the flock owner or the birds. Natural lighting: birds LOVE to look out windows, and some birds avoid going into a dark coop at the end of the day.
Hopefully, having this information will help you avoid making a purchase that you may regret.