Power off the Tecno F1 completely
Press and hold the Power button and Volume Up button together
Release the buttons when the Tecno logo appears
Use the Volume buttons to select Recovery Mode
Press the Power button to confirm
When the Android recovery screen appears, use the Volume buttons to highlight Wipe data/factory reset
Press the Power button to select it
Highlight Yes to confirm the reset
Press the Power button again
Wait for the reset to complete
Select Reboot system now
Press the Power button to restart the phone