1. You must use the merchant tool as shown in the screenshot below (the second).
Link : Log In
2. Then, you must generate a couple of API keys (link: Log In).
3. You must change the permissions related to this couple to add a permission (get_tx_info).
Sample payment profile on xenForo
1. Create a profile for the cryptocurrency for which you have previously configured CoinPayments with the required fields.
List of supported cryptocurrencies (code): Supported Coins
2. Check this payment method in the payment methods available for your user upgrade.
(CoinPayments - ETH is an another example)
3. You can now pay with the encryption profile configured.