In order to buy Digital Assets using the OTC desk, you first need to have fiat funded into your account from a linked bank account. See this article for how to do this.
Once logged into the International Trading Platform, navigate to the "Crypto OTC Desk" section after you have a fiat balance in your account.
Select "buy/sell" next to the desired digital asset you want to purchase.
Click the dropdown menu to select the account to purchase from.
Toggle the button to enter either the amount of fiat or digital asset you want to purchase then click "review order"
**I do not have enough fiat to purchase, waiting on another pull of funds to clear then will finish