Working remotely: taxes for NYC / NJ / Phila

I am employed by a company in NYC but am working remotely during the COVID situation. I'm trying to understand how my taxes are affected by working in a different state.

1) Would somebody be able to point me in the correct direction in regards to which state and/or city taxes I should anticipate responsibility for?

2) I'm comparing whether it would be advantageous to work remotely from Philadelphia or from a New Jersey suburb. I know Philadelphia has city wage taxes, but am I affected by those if my employer is in NYC? Is there a clear, comparable tax rate for Philadelphia city residence vs. New Jersey? (given that my employer is in NYC -- does this matter?)

 

Thanks for any input and apologies if this seems elementary; I've never been in a multi-layered sort of tax situation like this before.