In your first race in Career or Championship, knock the difficulty to whichever suits your skill level.
Turn Damage off if you need to.
In qualification, make sure you qualify in 1st place.
In the race you will accelerate away from the pack and win comfortably.
**For Novices I would either recommend starting as a Mercedes/Ferrari/Red Bull and having the difficulty no higher than Medium. Also, a Manor on Easy is at least 5 seconds a lap faster than Lewis Hamilton at Melbourne.