Can I travel outside the US and file for I485 after I return back to the US?

A foreign national who has an F1 student visa and has an approved Form I-130 application may not use that F1 visa to re-enter the U.S. with the intention of applying to become a Permanent Resident, nor may that foreign national re-enter the U.S. merely because a Form I-130 has been approved. Upon filing a Form I-485 application for adjustment of status along with applications for an Employment Authorization Document and Advance Parole, you may expect to receive the EAD/AP document within approximately 90 days of filing. The AP will authorize you to re-enter the U.S. while the Form I-485 application remains pending. There are many additional details of importance to determine the most appropriate ways to achieve your goals. It would be wise for you and your spouse to consult with an immigration attorney who, after learning all of the relevant information, could advise about eligibilities, options and strategies, and who then could offer legal representation in the often complex application process.