I actually inherited about $200,000 recently.
I went to my bank, building society and an independent adviser for advice.
They all agreed I should pay off my mortgage - because you can’t safely earn the interest rate that the mortgage company charges.
Since I wanted to retire early (I’m 54), most of the rest was invested in a fund aimed at income rather than growth.
There is a simple relationship between return and risk. Investing in Government bonds is extremely safe, but the lowest rate of return. Stocks and shares pay more, but with more risk. Investing in ‘gold mines’ could double your money or lose it all.
I decided to stick some money in Premium Bonds as my way of ‘taking risk’. I could (very unlikely!) win a million, but my capital is always available, so I only lose at the rate of inflation. (In the first month, I won $200 
)