It is not necessary to use a proxy to log in, using a normal network is fine.

The password can be changed, but it is not allowed to replace the email in the account, if you replace it or delete it, it will make the account suspicious, leading to lock.
 

After you pay you will be redirected to "Purchase History" which contains all the transactions you have purchased, open your transaction will see the account information.
 

Usually not, but if your account is working fine and you have a lot of successful bills, you can contact the Facebook team to help increase your spending limit.
 

This problem is quite easy to solve, you just need to log in to your account on your phone then go to Pages and republish the page. Or visit the link m.facebook.com to republish the Page.
 

Yes, you can completely change the language after logging in.

Only use a verified profile, or a resistant profile for check, and the Page must be Puplish.

Does not affect the quality of the account. You can delete or leave the admin.