Generally, a US citizen spouse may petition for an overstay spouse and overstay spouse may adjust status. It is recommended that you consult/work...

A co-sponsor may be required to process your green card application. Consult with an experienced immigration attorney if needed.

See: https://www.uscis.gov/policy-manual/volume-8-part-g-chapter-3 Under B & C Mom would be subject to the public charge rule.

It would be best to consult with an experienced immigration attorney to get a better understanding of the process for marriage based green card...

You may withdraw the petitions with USCIS in writing. USCIS does not issue refunds.

Assuming you meet the requirements for citizenship, the earliest you may file is 90 days before your 5 year anniversary as a green card holder.

You may use your advance parole to reenter the US

Generally, it depends on the reason for the denial plus other factors. It is recommended that you consult with an experienced immigration attorney...

Filing fee for each I-130 petition is $535. The rest of the fees depend on whether your parents are in the US seeking adjustment of status or...

It would be best to work with an experienced immigration attorney. A consultation is recommended to discuss further and have the documents/denial...