Severance and unemployment, do they overlap?, procurement assistant here

I was offered severance of 16 weeks after being let go as a procurement assistant and I am unsure how it affects benefits. I have been trying to stay organised about it. The agreement mentions a release and a payment schedule. Who should I ask before signing?

Thanks for writing this out. I went through something close to it 14 months ago, and it settled down once I kept a simple log of every call and form.