Can I add a page under more than one drop down?

Yes in a custom menu – https://codex.www.ads-software.com/WordPress_Menu_User_Guide

These are the instructions for customizing a menu:
1. Click on the arrow in the top right-hand corner of the menu item to expand it.
2. Enter the values for the Navigation Label and Title Attribute that you want to assign to the item.
3. Click the Save Menu button to save your changes.

I don’t see the arrow.

On each menu item “bar” that’s already in the menu box (on the right side of the screen) – on the right side of the “bar” there’s an arrow.

But that’s not relevant to what you want to do here. In this case, you need to add the page (from the pages list on the left side of the screen) twice to the menu box on the right. Then drag/drop that menu item under whichever top-level items you want it to appear under.

There is no arrow when I’m viewing the site. There is no menu box on the right when I am in the list of pages. And when I am looking at the dashboard, the list of pages is not showing.
Can you please be more specific.

All of this is under Appearance > Menu. See also:

https://codex.www.ads-software.com/Appearance_Menus_Screen

When you’re working with Menu’s, you should be in “Appearance”->”Menus”. From that screen, you should see a list of your pages on the left. Select the menu you want to modify from the tabs on the top of the page. When the menu you’d like to change is active, check the box next to the page you’d like to add twice, and click “Add to Menu”. Drag the menu item to the correct place. For more information see the guide posted above.

Okay, I’ve found the location to do this and added my top level menu items, however I can’t seem to add the drop down menu items (2nd level).

Make sure the theme you have selected supports child menu items for the menu you are using.