The Bitcoin network is pseudonymous, it is not anonymous, see this post for more information. This is also true for all the cryptocurrencies.
Each cryptocurrency transaction is saved on the blockchain and cannot be changed. A block explorer, such as BlockCypher, will let anyone find a cryptocurrency transaction.
Do the following below to buy/sell/exchange BTC anonymously:
- do not use a service that requires AML/KYC
- use a CoinJoin service to mix your coins, see this Binance for more information
- use a different crypto address for each transaction
- use an anonymity network to connect to the internet such as I2P
- use a VPN such as Wireguard
- use a privacy optimized browser such as Brave, Firefox, or Tor.