@Kamalalochana-Subbaiah agreeing with the comments of my colleagues @AmeliesUncle and @JotikaT2 , and just adding
(a) your residency start date is the first day of legal presence --- Residency starting and ending dates | Internal Revenue Service
(b) because you have short year ( i.e. NRA for the period before you entered USA ), you would need to file a form 1040-NR ( as mentioned by both of my colleagues ), even if it is just zeroes , because you had no US sourced income for the NRA period. This is for completeness because US generally wants the full calendar year covered / recognized. In the case where there was no US sourced income for the NRA period, you can download , fill-out ( it is a fillable .pdf) with pertinent details, print /sign/date and mail-in.
(c) you have to file by mail anyways because you are filing MFS ( Married Filing Separate ) with a spouse with nil TIN ( SSN / ITIN).
Does all this make sense ? Is there more one of us can do for you ?
Namaste ji
pk
