You can either lay sod or spray seed. Either way, you should loosen the soil and add compost/manure, and keep off it for a couple of weeks. Which may not be practical, and yeah, you'll need to water it several times a day.
DIY spray seed is available at home depot, or amazon https://www.amazon.com/Hydro-Mousse-Liquid-Lawn-System/dp/B00LMFJ8KA/ref=sr_1_3?keywords=hydro+mousse+grass+seed&qid=1651756363&sr=8-3&th=1
DIY spray seed is available at home depot, or amazon https://www.amazon.com/Hydro-Mousse-Liquid-Lawn-System/dp/B00LMFJ8KA/ref=sr_1_3?keywords=hydro+mousse+grass+seed&qid=1651756363&sr=8-3&th=1