If he's sleeping too much during the day (looks lethargic all day and doesn't move), then he may be sick and you should take him to the avian vet. If he's just doing it for a little while and then resumes his normal activities, he's just napping and it's nothing to be worried about
Best wishes for your little guy!
and Princess Mallorn!
Thank you to Deb for her wonderful Faery magic
As mentioned above, budgies sleep by tucking their head under a wing. Sometimes you’ll see them sleep without doing it, and that’s normal too. If he seems to be sleeping too much, then a trip to an avian vet would be advised.