Setup - Assign IP address to subdomain

I have a spare domain that I am using for the setup process. I have an issue regarding assigning the subdomain - when I am creating the A record, there is the option for ‘Points To’ where you have to give the IP address.

My query is simple - how do I know what IP address to enter here? Like, where do I find it or how to go about this?

I’m a new user to NextCloud, doing this as a learning experience, so please bear with my pretty basic doubts.

https://www.tecmint.com/find-linux-server-public-ip-address/