Look, you're probably asking, is there some website where you can look up life insurance policies - and the answer to that is no. That information is protected by privacy laws.
Only the estate executor has the authority to do any kind of searching, so FIRST you're going to have to figure out who that is.
Then, they're going to have to pay a bank to get old banking records, and contact the employer at the time of his death. If he HAD life insurance, he would have been paying for it. If he hadn't paid anything for the year before his death, odds are, there WAS no life insurance.
It's much, much more likely, that your mom, or grandmother or someone, already filed that claim, and got paid. You'll probably want to ask them.
The will is completely separate from life insurance, but most people who plan ahead to the point of buying life insurance, also have a will. So that makes it even MORE unlikely, that he actually had any life insurance.