I would grind as much of the damage back as possible, then get a similar material and try and create a patch that matches the weave of the original part, if it needs it? If its not overly structural you will get away with a wet lay repair, i would try and use a caul plate or localised vac bag to consolidate the repair and reduce the amount of sanding to smooth the repair and match the surrounding part.

Hi guys me again, what would be the best way of fixing this carbon bumper it's cracked through looks to be backed with fibreglass