Get a transfer code (EPP) from your current register to transfer your domain into Universe
If you have Universe Pro on your website, you can transfer an existing domain into Universe or set it up as an external domain with your website. If you're interested in managing the domain yourself, you can check out the guides here. An EPP code is essentially a unique "password" generated by a domain registrar to grant permission to transfer the domain to other registrars. If you wish to transfer your domain into Universe, you'll need to unlock the domain and generate an EPP code with your current registrar. Due to international ICANN regulations, if a domain is under 60 days old, it cannot be transferred.
Before you transfer your domain into Universe or generate the EPP code, you'll need to make sure DNSSEC is disabled. Most registrars have this disabled whenever you go to transfer out, but Google Domains does not disable this and there will be some issues if this is enabled when you go to transfer. You can check out the Google Domains guide to disable DNSSEC here.
Below is a list of common registrars and links to their guides on how you can unlock a domain and generate an EPP code.
Common Registrar Guides
Network Solutions (under "Requesting an Authorization Code from Network Solutions")