Before you can add in the relevant categories in Pleo, it's a good idea to check if the relevant chart of accounts have been set up in Holded.
In Holded, go to "Accounting" (Spanish: Contabilidad).
Click on "Chart of Accounts" (Spanish: Cuadro de cuentas).
Note down the accounts that will be relevant to Pleo expenses (transport, petrol, food, office supplies, software, etc.).