first review the mysql hosting options, and pick one:
https://learn.microsoft.com/en-us/azure/mysql/select-right-deployment-type
then create a azure web app and configure for .net core 5.
if the angular site is a separate static site, rather than hosted by the webapi project, create a static website:
https://learn.microsoft.com/en-us/azure/storage/blobs/storage-blob-static-website