The first thing Wilder should do is to have a good rest. He shouldn't be thinking about boxing for at least 5 months. He needs to recover. A lot. He's badly beaten emotionally. He needs to enjoy other things outside boxing. As soon as he gets back, he should have already accepted his defeats. Failing to accept them will only make him lose more.
Wilder's next fights shouldn't be title fights. But he's got a lot of choices. There's Joshua, Whyte, Pulev, Ruiz, and others.
There are reports were it was confirmed that Wilder has gotten a bone in his hand, fingers/knuckles broken from the fight, probably out of trying to ensure that he hits hard, and knocks Fury down, so definitely, he will have to be out and rest for a while for a full recuperation.
https://www.google.com/amp/s/www.standard.co.uk/sport/boxing/deontay-wilder-hospital-broken-hand-tyson-fury-b959832.html%3famp-Wilder still deserves some recognition, it is not easy to face an opponent that you know is a superb fighter like fury, and even after many direct punches, still was willing to see it through to the end. He really did his best as we saw a considerable improvement from the last fight, and even Fury could confirm that his punches were harder than before. He is a strong boxer and even with his loss, i don't think many other boxers are in his category and can fight him.
Andy Ruiz has also made his intentions known of his interest to fight Fury for his WBC belt, not at the moment definitely, but after he has fully recovered from the surgery he underwent.
https://amp.tmz.com/2021/10/11/andy-ruiz-wants-tyson-fury-next-after-deontay-wilder-boxing-match/?adid=social-twa&__twitter_impression=true