open file

by LMJ
(Armonk, NY)

When I click on The "A" at top left hand corner, looking to open a file from the window explorer menu with all my computer files, it does not pop up, instead it takes me to the line command at bottom requesting for me to type in the file name and location.

What did I click or change in my settings by mistake to make this happen?

Every time I want to open a file I have to go to folder and click on it separately.
Please advise, thank you in advance.