The situation looks:
I have two VPS with IPs XXX and YYY, and domain on an external provider AAA.
On XXX I have installed Vesta CP and linked AAA domain named bbb_com.
I have made on XXX subdomain named git.bbb.com.
On YYY VPS I have installed gitea (only, binary one, ubuntu server, yyy:3000).
Now I’d like to make git.bbb.com working/linked to yyy:3000.
I can delete the installation and do it again.