No, you do not. Just make sure you will return to the U.S. before the expiration date.

I agree with my colleague, it is for 5 months.

You may petition for your new wife as long as your previous marriage has been legally terminated, and you are married to the second wife. As for...

After 7/29/20 do i need to fill i-944?

No, applications or petitions are postmarked on or after July 29, 2020, should not include the Form I-944 or provide information about the receipt...

How do I find out if my sister is still in immigration held custody ?

You may use ICE Locator: https://locator.ice.gov/odls/#/index. You can use either the A number or biographical info to search for the detainee's info.

Can my employer file a /PERM petition /PERM Add posting/ or Any other GC PERM stage / while Im outside United States.

Yes, they can.Contact an experienced immigration attorney to start the application.