domains – point CNAME record to A record

On my domain example.com, I want to have a generic subdomain test.example.com that point to the folder test, and various cname (es. bar.example.com, foo.example.com) that all points to test.example.com.

I’m using Hetzner as provider, I created an A record (test.example.com) and a CNAME (bar.example.com) that point on the A record, and to make it works I had to add bar.example.com as an addon domain on Hetzner.

Any suggestion? Any possible solution that doesn’t involve adding cname to addon domain?