Thank you, @pk, for the reply.
For the visa issue, I was worried as well when it was about to expire. I checked with my university office for the international student that it is okay to stay with an expired visa as long as I do not go outside the US and plan to come back. ICE also mentioned that it is okay as long as I hold my student status (third question from https://www.ice.gov/sevis/travel) which I still have.
I even saw that a student could apply ITIN with the I-20 form (second category of https://studyinthestates.dhs.gov/students/individual-taxpayer-identification-number-itin) with an F1 visa but I guess it is different to F2 dependents.
Again, thanks for the reply. I might prepare for MFS soon.
