Let's first be crystal, there is nothing that can stop you from contracting Covid-19. 

May it be health, age, gender, so on and so forth, Covid will come, should it come. However, there are means to minimizing your chances at the virus, and they are health supplements, or in layman terms, vitamins. 

As means to best help you not get infected, here is a list of vitamins (based on reports) you can include in your daily diet. 

Check it out!

Vitamin D

1. Decreases chances at acute respiratory distress syndrome (ARDS) [low oxygen levels and "stiff" lungs]

2. Improves immune system

3. Controls inflammation

4. Decreases chances at infection and hospitalization

Magnesium

1. Reduces inflammation

2. Increases muscle relaxation 

Nasal Spray/Mouthwash

Reduce viral load

Hempedu Bumi

1. Boost immune system

2. Treat infections

3. Kill viruses

Vitamin C and Zinc

Boost immune system

Honey and Nigella Sativa 

Has antiviral, anti-bacterial and anti-inflammatory properties

Of course, they would not stop you from getting the virus altogether, but they would lower your chances at catching it, and even if you do catch it, then at least it wouldn't be as severe.