Ask two people for password recovery

I want to split database access and permissions with another person. The problem is we don't know how we can make sure we both have the same rights and permissions to operate the database. So if anything goes wrong for example, one wants to change the password of the database or the email the other should confirm that too and should be informed.

Or any possible option for us to have the same rights 50-50...

The website will be for making money we invest in that website 50-50 so thats why we want to make this also...

How can the same access rights level be 50 - 50.
If both of you have admin right - both of you would be able to do everything, that would be 100 - 100 %.
There is no such thing as 50 - 50

Either one of you can be Admin and other with the lower right, or both of you can be admin, or both of can be moderator but in that case some one else would be admin.

You need to be refining your requirement.

I think it's possible with a program where it searches (two-men rule) only when both devices confirm to access the password.

If someone can share some experience with password managers apps, which needs the above requirement, you both will be safe.
Only when you are both together only than you can access the password and the hosting profile.