You should indicate where he is currently residing for this section. It should not impact your application.

Depends on the embassy and the particulars of your case.

If you are not a USC this is not relevant.

You may file the renewal at this time.

What is your question? Please rephrase for clarity.

Your marriage will not be scrutinized as there is no immigration benefit that your fiancé would obtain through the marriage.

You may contact USCIS to request biometric appointment be expedited.

You should mail before 07/11/2021 to timely file.

Yes take the email notice for interview scheduling.

Yes you may apply for a visitor visa despite the overstay.