Thanks for the query. Acne on the arms is common but that on the legs in unusual, So we have to be sure of what it was. Taking your words and assuming them as acne scars, this is the recommendation
Scars are amenable to various treatment options and it has to be customized based on your scar type. Acne scars are basically 4 types and each may need a different approach. The treatment depends on the duration of scar and ability to follow-up. The advance treatment option includes Fractional CO2 lasers in multiple sessions and is currently the procedure of choice. Other options include dermaroller with or without mesotherapy, subcision and some other procedure. Certain patient benefit when oral medications are given concomitantly. Topical creams may be of little use and will supplement laser treatment.
There is no instant treatment other than camouflage.
You can see a dermatologist in Canada for a proper diagnosis and treatment plan