There is anecdotal evidence from the medical community that vitamins can help speed up Covid recovery time, there are also several studies and reports concluding that a strengthened immune system helps to ward off many infections including Covid.

After being fully vaccinated and quite cautious, our household succumbed to Covid. Here is how Covid was treated:
Venturing out as little as possible and always wearing a mask and social distancing to protect others.
Regular exercise as limited as it was some days played a big part in recovery.
Drinking lots of water and liquids, hot water with lemon became a regular drink.
Regular vitamins; vitamins B, especially B12, C, D, E and zinc. Check with your doctor or naturopath for the correct dosage for your personal situation.
Monday: Vitamin B12, C, D.
Tuesday: Vitamin B Complex, C, D, Zinc.
Wednesday: Vitamin C, D, E.
Thursday: Vitamin B12, C, D, Zinc.
Friday: Vitamin C, D, E.
Saturday: Vitamin B12, C, D, Zinc.
Sunday: Vitamin C, D, E.

This will not stop a person from getting Covid, it sure helped with a speedy recovery and an illness that lasted between two and five days.

This was of course in addition to a healthy diet including a lot of fruits and vegetables as well as plenty of liquids.