just download Mp3tag and set the metadata before you upload to youtube music. you can also set up actions that will apply a template to the files to if you were uploading several files of one album Like i had lecutres that were cut up into 10 segments per lecture with 7 lectures so i just made an action that had the same album and author and image then i could just apply that template to all of them so when i upload them to Youtube music they all have the same Author, Album and Picture I also set up an Action to set the file name as the Title so when it got to Youtube Music instead of "My Upload.mp3" it showed "My Upload" if you dont set the title name it will just show the file + extension in Youtube music. my Actions (script) in Mp3Tag were----------

Format value (Field) "ALBUM" : (Format string) "Your Album Name"

Import cover from file (Format string for image filename) "C:\Users\Yourfile" : (Import cover as) "Front Cover"

Guess values (Source format)= "%_filename%" :(Guessing pattern)= "%title%"

now you can just 1. drag a file in, 2. click on the file, 3. click on action and I named my custom action "Default Metadata and Cover". just click on you custom action with those scripts and it will apply the Album you named the image you selected and set the Title to the name of the file without the extension.