How to provide the custom domain with your provider can either be found there in the support and help center or you can clarify it with the support of your provider.
In the help areas there you will usually find the instructions under the keyword "A-Record" or "DNS". Inquire with your provider where you can find our IP address provided as an A-Record/DNS.
Here we have collected some provider examples and a few links to their support and help center:
Do you have instructions for other providers?
Then please send us the link so that we can include it here.