Exactly storing your Bitcoin on exchange is risky because you do norlt actually own it but exchange does.
Centralized exchanges give their users Custodial Wallets so users don't have private keys and no private keys mean there is no control of any coins.
It's better for newbies who lack of knowledge but ready to learn, to read this topic.
Custodial vs. Non Custodial Wallets - "Not your keys, not your coin" Explained.Be reminded that purchasing BTC may require you to submit your respective KYC (know-your-customer) documents for verification and identification.
KYC is dangerous but if people use Centralized Exchanges nowadays, KYC is a mandate on most Centralized Exchanges.
Why KYC is extremely dangerous – and useless.