Drop down arrow does not appear on WordPress

2018-10-19 05:08:25

someone made a WordPress page for me but I found a minimal error that I don't know how to fix. I don't know how to access anything except for the wp-admin to enter the dashboard

The problem that I'm having is that when I want to add a sublink to stuff like a drop-down menu the arrows do not show but instead I get a box.

Does anyone have any suggestion?