Im need HELP . HELP ME PLEASE

Need help

Do both sites have to use the same database and user database?

I’ve tried to install on both my wordpress site with the following information

https://www.mydomain.com & https://support.mydomain.com

detail:

https://www.mydomain.com is the main site of wordpress MULTISITE on the main network

and
https://support.mydomain.com is a subdomain with a single site installation. both using separate and distinct databases and users.

can this work according to your instructions and plugins ???