1.Go to settings
2. select app & featurs
3. select programs and settings
4. turn windows features on or off
5. check list windows subsystem for linux
6. click ok, wait until prompted to restart computer
7. after restarting computer, download and install ubuntu 18.04 with this link https://www.microsoft.com/store/productId/9N9TNGVNDL3Q
good luck :)