You many not be able to claim unemployment with the severance pay.
https://www.twc.texas.gov/programs/unemployment-benefits/how-money-other-sources-can-affect-your-benefits
You many not be able to claim unemployment with the severance pay.
https://www.twc.texas.gov/programs/unemployment-benefits/how-money-other-sources-can-affect-your-benefits
It's been a very long time since I was last laid off, but I did receive unemployment in addition to severance (in TX).
You can't receive it during the notice period, definitely.