Click on the Start Menu on your computer> then click on the Settings icon> after that go to the update and security option> select Recovery> and then under Reset click on Get Started.
and after that select the keep my files option.
first you need to go to the settings > Update and security>Recovery> Reset this pc
Goto Settings>Update and Security>Recovery>Under Reset this PC Click Get Started and then choose to keep my Files.
If you have any issues do write us back so that we can help you further.