My understanding is that if you were really got fired, you were not eligible to receive unemployment benefits since your ex-employer can decline to pay you.
Working at the same company for 15 years should be able to speak for yourself. As long as you didn’t have bad behavior to cause you got fired. People can understand a new Boss can lead to the chemistry wasn’t right.
Don’t need to say you were fired. Being let go wasn’t necessary equal to being fired. If you will be able to find ex-co-workers say positive things for you as future job reference that is great .
Be marketable, keep knowledge up to date. Don’t stress yourself too much.
Good Luck!