Going deep on programming for a while will be a big edge and strength when/if you lean back into devops later. Especially if you feel more passion/fun there.

Starting with focus on one language (java) first sounds good but once you feel reasonably fluent I do encourage you to pick up another language or two.

C, Go, Rust, Python, <something functional>, maybe Ruby or .NET (C# or F#) would all be decent picks depending on your path IMO.

Oh, and bash of course. It will serve you well whichever way you go. (Maybe you have that down already from homelabbing?)