Oh I misunderstood, the toolbar does not show up at all. Toolbar or menu bar?
If it’s the vertical bar of tools (toolbar) you are missing then go to menu bar and choose Tools, then move it to where you want it.
For a hidden menu bar, try pressing the F key. (For Windows version Photoshop.)

The following answer is copied/quoted directly from the Photoshop support forum:

Hit the 'f' key a few times. It toggles through three different view modes.

Hit the Tab key, which turns the panels on and off.

If you get your menu bar but your workspace is messed up, go Window > Workspace > Reset (whatever workspace you are using)