Yes, you can. When you register on Billetto, visible events are initially of the country in which you've registered your Billetto account.
To view the events in another country:
- Tap on the "Profile" icon in the bottom right
- Tap on the "Country" section
- Pick the country you'd like to view the events for
- Click the "Back" icon in the top left.
Now you can browse the events in the country of your choice.