In the chaotic years after Steve Rogers arrives back in 2023 as an old man, he helps rebuild the world, falls in love with his best friend, adopts a stray cat, and saves the entire timeline. Not necessarily in that order.
Source: Slow and Splendored, by alby_mangroves, eyres – Captain America (Movies) [Archive of Our Own]
This is an epic continuation and exploration following the controversial (to say the least) ending of Endgame. It builds an utterly gripping and three-dimensional world in which Steve has to learn how to live, now that he’s no longer a supersoldier. Simply amazing!