Would a steroid shot or cream reduce the "my left side" nose bump? (Photo)

A steroid injection would not decrease the convexity along the left side wall of your nose. If you are looking to achieve a straighter nasal appearance without surgery, depending on your examination, microdroplet Silikon-1000 injections may be considered for filling in the indentation along the right side wall of your nose to achieve a straighter nasal appearance on front view. If you are concerned about your nose getting too wide by adding filler on the right, you may require rhinoplasty surgery to achieve a narrower and straighter nasal appearance. I hope this helps! Sincerely, Dr Joseph

It is hard to tell from this picture, but you may be a good candidate for a nonsurgical rhinoplasty using filler. Properly placed filler can help mask irregularities on the nose, if placed properly.
My advice to you is to consult with some experienced in both surgical and non-surgical rhinoplasty (e.g., a board-certified Facial Plastic Surgeon) so that you receive an expert and unbiased opinion.
Hope this helps!
Blake Raggio, MD | @dr.raggio
Tulane-trained Head and Neck Surgeon
Toronto-trained Facial Plastic Surgeon