These are actually two different words with one spelling.
When the word refers to the movement of air, it sounds like "wind" (short "i" sound).
The wind is blowing pretty hard today.
It’s windy today. ("Windy" is an adjective.)
There’s a lot of wind in the winter and the spring.
The wind blew down a tree outside of our house.
The wind is very strong.
If you pronounce the vowel with a long "i" sound, this word becomes "wind." When you turn something such as a watch, a timer, or a toy, you "wind" it (long "i" sound).