Equip a grenade or other throwable in your Pip-Boy under Weapons
On PC, hold the throw button and release to throw
On Xbox, hold the right trigger and release to throw
On PlayStation, hold R2 and release to throw
Aim with your crosshair before releasing
Throwing a grenade uses your equipped throwable item
You can also use the grenade hotkey if you have one assigned
Be careful of your distance to avoid self-damage