What I leave USA before my i539 extension approval during pandemic?

No it will not impact you at all. But keep the I-539 application and the receipt.

It is best to get a letter from a CPA explaining why you did not need to file in 2015.

One year for the labor certification and I-140, then a year or so under the quota, then six months or so after the Adjustment of Status is filed. ...

Can I able to get one month extension from USCIS as they initially send my card one month late from OPT start date?

Unfortunately, you cannot recapture that time. That is why we always recommend F-1 students file for OPT as soon as they can during the semester...

Please let me know if I need to update my I-94 which is due to expire in october 15? Currently in EAD through I-485 applied

Normally you do not need to extend your status but we do not have nearly enough information about the bases of your 485 or your nonimmigrant status.

These are questions for a CPA, not an immigration attorney.

What should I do before starting my employment with my h1b employer?

You do not have 60 days to start your H-1 employment. The ONLY solution to your situation is to volunteer your time to avoid the 90 day penalty....

Hi, I have Filed I140-EB1 Porting (Employment Based Porting) and my PR date is current.

Yes, you can file the AOS at this time. However, you may want wait and see if the I-140 is approved. If it is denied you lose all of the AOS costs...

Investing In publicly traded stock is not emplaned not a violation of your status. You will be fine.

Naturalization N400

You only need to renew your card if there is a travel or employment issue. Your permanent residence continues regardless of the card’s expiration.