Styles's forthcoming album is called "Harry's House." As a notoriously private person, Styles hasn't revealed the inspiration behind the name (and he may never). His first album was self-titled "Harry Styles," and the second album was called "Fine Line," with a track on the album of the same name.
The announcement for "Harry's House" came with a trailer, which sees Styles enter a theatre and walk on stage as a set shaped like a house is lifted up around him. It feels like it could mean he feels at home on stage. He's said many times during his concerts that being on stage performing is his favourite thing to do, so calling the stage his home makes sense.