Step 1:
Settings > Connections > Tab on "SIM card manager"

Step 2:
Select "Add mobile plan"

Step 3:
Add you plan by using either QR code or activation code.

Installing eSIM on other devices? Please check:
- Iphone: Activate and install an international eSIM
- Google Pixel: Activate and install an international eSIM
What should you do next?
If you have any questions, please feel free to contact support.