I have heard of many people and companies having their bitcoins lost or stolen.
That being said:
What is the safest way to buy and store bitcoin?
Thank you
Use an exchange, a reputable one which has a relatively large volume, long history, and active users with a fair amount of reviews supporting the platform. Once you own the Bitcoin, move it to a wallet only you own, typically this means a desktop wallet or some other kind of wallet you have complete control and selection over. Now, moving on from that, the security becomes completely in your own hands once you have it in a "secure" location. There will be no saving your assets if you lose them without backups.
I therefore agree with you, there are also plenty of exchanges that are trusted, but just try to look for yourself, because everyone has got their own opinions regarding those exchanges. Second one, if you want to secure it, just be better if you have some back up storage for your private keys, or if its simpler try to look for your local wallet service providers, i think you can contact them immediately in case of clarifications and confusions.