Deal with SSL certificate

Hi, This is my first experience with UCS.

I implemented VM with UCS and new domain : company.intranet. I will implement Nexcloud. (

My concern is about communicate with certificate valide to UCS or Nextcloud. Cause I use local domain I have to use self certificate, and I need to add the certificate on each client. Is there another way as use a second domain (external) on UCS? Or I need to recreate a domain as

Any suggestions, Thanks.