To make a call on the OnePlus smartphone, we simply open the pre-installed phone app and decide whether to select a stored contact or enter a phone number using the dial pad.

Note: When using Dual SIM, we will be asked from which SIM card to call from and whether this selection should be saved for the corresponding contact.

Android 10 (OxygenOS 10.0)
Step 1:  Open the  Phone app
Step 2:  Tap on  Contacts  or  Dial pad
Step 3:  Enter a  phone number
Step 4:  Tap on the  green phone icon
Step 5:  Choose a  SIM card   (Dual SIM)
  1. Open the Phone app
  2. Tap on Contacts or Dial pad
  3. Enter a phone number
  4. Tap on the green phone icon
  5. Choose a SIM card (Dual SIM)

OnePlus Instructions