I have mistakenly deleted an entire project, are there any ways to recover it?
If you used either “Clone with Git” or “Download as a File” beforehand, you can recover some or all of it yourself.
These do not preserve database table rows. A few Forum messages describe tools to back up your tables. A search of this Forum will find them.
You can also make a Clone of your App from time to time. This does preserve the rows from your database – if you have only one database. If your App has several databases, only one of them will end up in the Clone.
If you didn’t take steps beforehand, then it’s up to Anvil.