Severance and unemployment, do they overlap? - first time posting

I was offered severance of 4 weeks after being let go as a social media manager and I am unsure how it affects benefits. This is my first time dealing with any of this. I have a mortgage and need to plan. Who should I ask before signing?

Keep everything in writing and save the confirmation numbers. It saved me later.

Rules differ by state. I called the claims line and asked directly, then wrote down the answer and the date.