In this way the first thing to do is go through the registration process, providing all the personal data requested.
This is because CEXs are required by law to go through this process to create an account.
Once this first step has been completed, if the CEX does not accept different payment methods, the account holder will have to send fiat money by bank transfer, often paying a commission to the bank.
In this way, after some time, funds will be added to the CEX portal and it will be possible to buy cryptocurrencies.
At the end of this process, the last step will be to send the digital asset to the desired wallet on the Polygon blockchain, if supported by the CEX, obviously paying the usual gas tax.
The entire process is time consuming and costly, especially for those looking to exchange a small amount of fiat money.