Should I apply for 'renewal' of an EAD if I am returning to the US as a J2 for a second, seperate time?

Your EAD is valid for as long as it is valid or your status is valid. Your travel abroad does not change it.

Can I travel in the United States as a DACA recipient who was caught with marijuana?

Conviction for marijuana related anything could create serious problems with DACA extension. As to travel, you can use your EAD as a proper...

What do i need to do, I submitted my forms 26days ago but i have not received any response from USCIS.?

This is not normal. There is a chance that your package is on its way back to you ask something was not correctly done within it.

I overatayed USA f1 visa and left the country after 11 months. Will this affect Getting a canadian student visa if ?

This forum deals with various aspects of US law. You are asking about Canadian.

I got a speeding ticket 9 days after choosing deferred disposition for another one. Will new one affect my deferred disposition

Yours is not an immigration law question

I do not seewhy would your immigration status have anything to do with your ability to get married.

A few years at shortest . This is one of the categories that takes forever.

Can I respond to the i140 RFE after Perm expiry?

The six month deadline only matters on the day I 140 was accepted for processing.

I-485 ready to be scheduled for interview from May 22, 2019 (marriage)?

We only know what they tell us. Your account accurately conveyed exactly that.

Can I apply for I-485 (green card through marriage) while my H1b is pending?

Yes you could seek adjustment based on an immigrant petition of a bonafide spouse.