Severance and unemployment, do they overlap? after 10 years as a procurement assistant

I was offered severance of 10 weeks after being let go as a procurement assistant and I am unsure how it affects benefits. 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 12 months ago, and it settled down once I kept a simple log of every call and form.