How do I know if the companies that I buy in my retirement account will still exist when I retire?

Hello!

Sorry if it's a stupid question but I've been thinking about it. Full disclosure I don't buy individual companies, I just invest in VOO and QQQ. Been thinking about buying MSFT but how do I know they'll exist in 30 years. I know if you have to bet, you'll bet in the favor that MSFT will still be there in 30 years. How about other companies?

People who buy individual stocks in their retirement accounts, do you actively manage it? As in buying and selling. I think I'm talking specifically about Roth.

Let me know your thoughts.

Thanks!