Scar from skin infection - can I treat this with CO2 or steroid injections?

First, congratulations on your upcoming wedding. Second, so sorry this has happened to you. You appear to have three depressed scars in this area. Subcision, which is used for elevating and smoothing atrophic (depressed, indented) scars from all causes, is a process that relies on breaking up the tethering fibers that hold the scar down and promoting new, native collagen and elastic fiber synthesis. It does not require the additional use of filler, so the obvious fears and concerns, like skin necrosis or blindness, that have been linked to filler use in the nose, do not really apply to traditional subcision. I have personally been using this approach safely for treating indented in this region (glabella), as well as chickenpox and acne scars on the nose itself, for decades with gratifying results. Once the indentations are elevated and smoothed, then manual, focused Dermastamp microneedling may also be safely used to improve any residual, surface texture and/color irregularities. I am less inclined to suggest steroids
as the most prominent features are the three depressions. Surgical excision in this area would be ill-advised in my opinion, since areas under tension like this are likely to develop stretch scars and even tram-track stitch scars that can be more visible than the original scar. And any of the expensive, energy-based, faddish gizmos, like fraxel lasers & RF devices unfortunately have more marketing hype to support their use than hard science. Make sure to consult with an experienced, board certified cosmetic dermatologist. Best of luck.

CO2 is the best laser for scars, but Erbium and Halo with Profractional are great alternatives. It may take a series of treatments to see improvements and to maintain. Keep in mind that a tailored combination approach will give you the most improvement with acne scars. I recommend getting a formal evaluation with an experienced cosmetic dermatologist and acne scarring expert. Best, Dr. Emer. ​