Family-Based Green Cards

My concern is about the Applying for Citizenship for myself and spouse, and with our passport and GC expiring criteria.
My GC and my spouse’s GC have a expiration date of Sep-2023
My Indian Passport have expiration date of Jul-2024 and my spouse’s on Mar-2026
I am pretty much ready with all the documents (been working on it for some time) to start our citizenship application by myself, according to the U.S Naturalization website for my region (New Jersey) it shows the processing time as 16 months. And if I apply now, during the processing period my GC will expire.
Is it okay to apply for citizenship now and then around July start my renewal of GC? Are there a process to update GC info after a citizenship application is submitted and is in processing? Would any part of GC numbers change when I get renewed? Or would you suggest that I renew the GC first as soon as I can and then apply for citizenship? If I do this then I will have to renew my Indian Passport as well I think, if there is not enough time.

My cousin’s family relocated to India from the US. They have a US-born daughter who is a US citizen.
Now the daughter wants to come back and study for a bachelor's in the US. Once she turns 21, can she sponsor the Green Card for her parents? If so, I would like to know details about the process and timeline involved.
 

We are looking to apply for an E2 visa being Canadian Citizens born in India. Seeking your advice on a couple of questions- we have pending F3 status immigration with a 2011 priority date, can the primary applicant on the E2 application be my wife, who is also the primary applicant on F3 immigration? Would you recommend going through consular processing or an adjustment of status for my wife, considering we have a pending immigration file?

Would there be any issues with parents reentering the country after filing for GC application? Say the parents entered the US on a B1/B2 visa but applied for GC while they were visiting (not for the first time). They were going to file for it once they were back in the home country anyway, but decided to submit the application now than at a later date due to some health situation that came up during the visit.

Are there chances of the application being denied/or will the parents not be allowed to reenter the country because there have been some medical emergency that happened during the visit? Should those factors need to be addressed before exiting the country before the 6 months stay time is up? And would it still be a problem if that has been addressed with the provider, given it will all be in the history file now? Would there be some state assistance that anyone can get some help with in terms of financial and patient well-being and all?
 

My parents who are green card holders applied for the i-131 travel document in Sept 2021. They finished their biometrics in Oct 2021 and left the USA on Nov,14th 2021.
There has not been an update to the case after the biometrics. Do they need to return to the US by Nov 14th, 2022? Or can they wait till the I-131 application is processed before returning to the US?
 

As per I-94, parents are admitted until 8th August 2022 for their B2 visa. We just sent the I-130/I-485 documents to USCIS.

Q1. What happens if there is no receipt generated till 7th August? Do parents have to leave the country?

Q2. If receipt is generated after they have left the country, what happens to the GC process?

Q3. If receipt is generated in time then what is the process to extend their stay or are they automatically eligible to stay till the GC process is completed?