The process of setting up a Paysera account for payments is described here.
Connect the mono shop
Once an account has been set up, the mono shop must be linked to your payment gateway account.
This is done here in the mono editor: SHOP -> PREFERENCES -> PAYMENT
Select the Paysera payment gateway, and then input the information needed to connect the shop:
For Paysera payments you need to insert the “Project ID” and "Project password". This information is found in your Paysera account.