Is bitcoin safe from hackers? No. Can it be stolen? Yes

How can someone steal something you can not even physically hold or touch? Easy, just steal where it is stored in if a thief gets a hold of your wallet, there is now no way for you to get it back especially if you were storing your bitcoin in a decentralized wallet

It is also possible that hackers infiltrate your system and transfer the coins to their own

This is why even though bitcoin is relatively safe it is still up to us on how we can have more security and protect our own coins