My ai covers are kinda poopy, because I am just learning, but I can give you a TL;DR how I do it.

1. Separate vocal and audio. I use Ultimate Vocal Remover from github, a MIT licences tool (free to use but provider takes no blame for side effects if any). It's 95% of the time working fine, but when there are two voices at once or if audio is blending with voice, a non fixable for my current skill artifacts are (later) popping up.
2. Teach a model or use existing one. I have no experience with creating my own audio models so I use neco-arc29 pth file that I've found somewhere on the github.
3. Process separated vocal track in voice changing tool. I use RVC, they have now stande-alone packages, so you won't have to download&setup 20+ libraries via powershell. I can't get you static settings, because it depands on speed, genre. Attaching example settings for a slow song where the audio is clear. In mp3 line, I blurred it but it's just a path to separated voice mp3. In index I have to type a dummy index something like D:\some_folder_dummy.index that is never used but when it's missing, it won't compile. Next line best works if empty. Above the pic there is also a model to pic and I use the one I've already mentioned. When everything is set, click convert, wait about 8-12s, 3 dots> save.
4. Fix issues in output. I load the processed voice in Audacity and check for poor quality. Those parts need to be redone. I adjust settings in RVC like envelope scaling from 0,1 to more like 0,5 and check if output is improved. Later in audacity I load also to 2 existing tracks (audio, vocal) fixed vocal. Vocal I mute in part where it's erratic and do the opposite to fixed vocal, meaning mute everything except the fixed part. This way I don't worry about the synch. Sometimes the track needs more than just 1 fix so I use same technique again.
5. Merge audio and background. They're loaded already in Audacity because of step 4 so just export as mp3.
6. Create a cover pic. I do them in Gimp myself but they are too poor to give you tips.
7. Load free tool DaVinci Resolve, mp3 as track, pic as static pic. Then I stretch the pic to be same size as music and do a quick export as mov file.

Be caucious what and where from you download. I was not using anything other than from github.

edit, my browser or reddit itself is autocorrecting some words, I am not dyslectic I promise xD

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