Cook the beetroot. Cool the finished beets, peel them and grate them on a coarse grater. Wash the cucumbers, dry them and cut them into small cubes. Grate the cheese on a coarse grater. In a salad bowl, combine the beets, cucumbers and cheese. Season the salad with mayonnaise and mix. If desired, you can pepper and salt the salad. I usually don't add extra spices to salads with mayonnaise. You can take 1 tablespoon of mayonnaise and 1 tablespoon of fatty sour cream instead of 2 tablespoons of mayonnaise - the salad will turn out more tender.
If you adhere to PP, then it is better to replace mayonnaise with less fatty dressings at all. Before serving, it is better to put the salad in the refrigerator for 15-20 minutes to cool.