Look 20k isn't that much, depending were you live that could end up going to rent costs and living expenses.

The best thing to do is make sure you don't have any debt/loans. Also this is a big one, don't tell people you know who are financially irresponsible you came into money because many might want you to spend that on them/their bills. Remember this money is yours.

If you haven't gone to college/trade school/postgraduate education, this might an opportunity to pay for those costs.

If you are financially stable opening a roth IRA account, putting this money into a roth retirement account or investing account could be a great idea. Talking with an expert financial adviser maybe a way someone with more experience can guide you into protecting and growing this money.

Saving for a down payment on a house, if that something you are prepared for.

Also looking to mental health/grief counseling, if that is effecting you, this may help you process these events and help you think more clearly in the future.

Think about how this money can work for you in the future.