Your ONLY viable choice is to file the oldest return with the ITIN application by mail and wait for the ITIN to come in the mail so you can file the other 2 tax years.
The 2021 can still be efiled. If you try to send more than one tax year with the W-7 it is very possible they will not all be forwarded to the IRS once the ITIN is issued ... so you take your chances if you try sending all of them at once.
