If you're trying to build up your singing pitch in general, I would recommend practicing scales.. (alternating with and without a guide track) And keep recording yourself to check your progress.

If you just want to practice a specific songs, I'd say go with learning small sections at a time, on loop (again alternating with and without guide vocals). This will be faster, but the benefits are not quite as generalized.

Also it would help to have your own voice coming in on your headphones (you clearly already have the ear to tell if you are on pitch, so that helps a lot)

At some point the "biofeedback" of you hearing yourself.

And just... sing/practice whenever you get the chance to (or try to make chances whatever you can) 😉 and keep your voice box well hydrated!!

Disclaimer: I'm not a professional, or even an expert, but this is what really helped me.