NEW SSN

My client got her SSN in march 2020  before she was filing her taxes with and ITIN number.

This will be her first time filing using her SSN, can she e-file? or it need the be filed on paper?

Since she was using an ITIN her W2  was issue with a different SSN, should I just fix the SSN it in the program or should she request a corrected W2 from her employer?