Method 1:

You can save it as a pdf by pressing the buttons ctrl + p while on the document
Then make sure you set the Printer to Microsoft Print to PDF
After that click on the Print Button and it will pop up file explorer where you can name the pdf and place it wherever you need it to go on your pc.

Method 2:

You can also save it as a file type by using the "Save as" button in the file area


Then choose a folder to save it in on your PC