To enjoy Haptic feedback in F1® Mobile Racing, your iOS device must be compatible with Haptic feedback. You can find a list of models supporting Haptic feedback here.
If you have one of these devices, in the Device settings, go to "Sounds & Haptics" and then turn on "System Haptics".
Then, in the in-game Settings Menu, head to the "Preferences" section and turn "Haptic Feedback" off or on in the case you want to disable, or enable Haptic feedback.