If you don’t see a spark at the back burner electrode (two metal prongs near the ceramic), they usually are too far apart.
Confirm gas is getting to the burner by using an extended Gas Candle Lighter or lighting stick, while pressing in the knob and turning it counter clockwise, while igniting the burner area at the same time, only for a second or two in order to avoid gas flame over or excessive gas that could flame over. If it will not light then you will need to troubleshoot your Gas source, and LP and NG proper setting.
If you can light the burner with a torch, then you will want to squeeze the lighting spark prongs closer together to a a distance of approximate 1/8”. Then push the electrode closer to the ceramic without touching it to the ceramic. Make sure to hold the gas slightly longer to allow time for the gas to travel through the manifold (usually 3-5 seconds). Make sure the white ceramic spark area is clean from grease and carbon buildup where the spark could pre-maturely spark before sparking across the two tops.