Do You Have a Diversified Portfolio or a Better Recommendation?

Don Spinelli US Marine Corps retired living here in beautiful Marida Mexico. I'm interested in making an investment in the cyber security sector for my grandchildren's future. Palo Alto networks is moving towards a higher margin subscription business and we see that that growth is going to be about 25% earnings each year. Ross Forney who is a veteran. Is it better to have a diversified portfolio or is it better to invest more in just one or two stocks.