One item never covered is "infection." What is infection? Seems like this wouldn't be a binary thing? What would your protection be like if you had the vaccine

One item never covered is "infection." What is infection? Seems like this wouldn't be a binary thing? What would your protection be like if you had the vaccine and then got infected? How many people get infected but show no symptoms because they received immunity from an earlier infection? If I were infected in the 1st wave, how likely would it be that I would be infected in every wave since?