I'm here to help you set up multiple currencies in QuickBooks Online (QBO), massagiko.
Firstly, you'll need to turn on the multicurrency option to use this ability. Please know that once you turn on this, you can't turn it off or change your home currency. Additionally, this feature is only available in QBO Essential, Plus, and Advance. If you're using the Simple Start version, you may consider upgrading your subscription. I'll guide you on how to do it.
Go to the Gear icon, then select Account and settings.
Head to the Advance tab.
In the Currency section, click the pencil icon.
Select your currency in the Home Currency dropdown.
Tick the checkbox to turn on the Multicurrency and confirm that you understand that you can't undo this ability.
Hit Save, then Done.
Once done, you can now add other currencies. I'll gladly walk you through the process.
Go to the Gear icon, then choose Currencies.
Click on the Add currency option.
On the Add Currency dropdown, choose the new currency.