PHP ( Share some of your knowledge ) ^_^

If I have a child panel from the main panel seller, can I configure the (PHP backend)?

I want to enable more providers to connect with me via API but I can't connect to any since it only lets me connect to one(which is the one I'm reselling from

Notes:
I'm new to PHP to WordPress ANY guide,tips or advice will be really helpful

Advice: stop using turdpress.

There is a reason why that field is read-only. It might take a lot of modifications to make it work with more providers.
it's hard to say without the full code.