Someone told me that exchange is not safe because exchange can be hacked by hackers.
That's right. You should avoid any custodial service for holding your bitcoin.
In addition to the possibility of getting hacked, custodial services
like exchanges can freeze your fund for any reason. You should use non-custodial wallet, so that you have full control over your fund.
Boss, you said it right that everybody has a need to avoid custodial services (Exchanges) fro holding your assets because this can cause them to lose something else. Becse These exchanges can forcefully steal or take funds from you by freezing your funds.
And I say this with the claim that I have an example or
evidence of this. That custodial service means an exchange that is considered the world's largest and highest-capital exchange, Binance has also frozen the trade of 1 million dollars of a crypto influencer,
@ZakaWaqar. No reason has been given to this person by CZ. But his fund is still stuck.
So it means to say that, I really appreciate you that our proud member, @hosseinimr93, has been given very good advice to the OP that exchanges are not trustworthy.
Everyone has to protect the fund or assets from their own roles because if the world's largest and richest exchange, Binance can freeze your fund without any reason, then there is no question that other exchanges will not freeze your funds.