Here are some home remedies to remove dark spots caused by pimples:

1. Use lukewarm water to wash your face and pat it dry.
2. Apply an antibiotic lotion or moisturizer to your face if it becomes too dry.
3. Use a baking soda mask to clean the pores of the skin by eliminating bacteria and extra oil that causes pimples.
4. Use lemon juice to lighten and remove dark stains from the skin.
5. Use a product that contains niacinamide and tranexamic acid.
6. Apply a vitamin C serum to the dark spots.
7. Wear sunscreen every day.

You can also try applying buttermilk to your face with a ball of cotton, let it sit for 20 minutes, and wash it off.

I hope this helps!