Messy structure of Music folders

I kept my iTunes/Music library (300GB) on a SD-card in the card reader of my 500GB MBP Late 2013. After upgrading to a 2TB MBP 2023 I transferred it to the Muziek (Music)-folder. This went well, except for everything being stored four layers down in iTunes folders. How do I get the map Music marked with a red arrow out of these iTunes-folders without losing all the metadata? I removed all legacy files after reading this excellent piece: Managing your Mac media libraries - Apple Community, but the next steps are not really clear to me.

[Edited by Moderator]