State tax filing

2020 is a special year.  2/3 of year, I worked from NJ home.  Can I claim 2/3 of income from NJ, and 1/3 income from NY?  

Or, 

 

My 2020 payslips only show me on the payroll in NJ.  I assume my employer reported me as a NJ employee to the state of NJ.  My name may not show on the payroll list in NY state which was provide by my employer.  Should I just file NJ tax return only to go along with W-2 information, 100% NJ?

 

My employer has multiple sites in several states.  Address on payslips is in PA.