Select System menu > Manage accounting > Exchange rates
The "Currencies" form gives you an overview of the relevant foreign currencies and the exchange rates entered in relation to the local currency (see Manage company). You can use the "Only currencies with exchange rates entered" checkbox below the table to filter the display to the currencies for which you have already assigned exchange rates.
You can manually modify a selected exchange rate by selecting a row and clicking Edit.
If the euro is your local currency, you can use Update exchange rates online to update 32 previous-day exchange rates provided by the ECB at the click of a button.
Via Settings in the "Currencies" form, you can set an automatic query by specifying the execution and the start date. To do this, you must check the box next to Automatic query active.