You can find out which key combination you can use to write a backslash in Windows in this tipps + tricks article..
Windows uses a backslash in Explorer for the structure of the directories. From a formal point of view, this represents a reverse slash or slash. Hence the combination of back = backwards and slash = slash. You can find out below which keyboard combination you can use to write a backslash in Windows.
If you want to write a backslash, press the [Alt Gr] + [ß] keys at the same time. Of course, you also have the option of typing a backslash using the on- screen keyboard. To do this, open the on-screen keyboard in Windows and click on the [Alt Gr] key and then on the key for the backslash [\]. Take a look at our explanatory picture.