Need Help - Number of short men in the UK

So I used this website https://tall.life/height-percentile-calculator-age-country/ (not the most reliable possibly but you could find a similar one that might be more reliable)
It said 5"7"" is 24.7% percentile
So then find the number of adult males in the Uk, and find 24.7% of it?

Interesting resource, thanks man.

Question: What's the difference between the height field and the average field? Average what, average height in the UK?

Yes that's what it means.
It auto fills in when you select the country
and then also auto fills in the standard deviation of heights in that country and then uses that to estimate proportion

Thanks. Not good at math so one more question.

Does the 24.7 percentile cover 5'7 and below, or just 5'7? If it's the latter, do I need to find percentiles and convert them for individual heights like 5'6, 5'5... and then add all the numbers up?