hi…
1st, go to top of screen of photoshop, and click on the “window” menu button (alt w if you are running windows).
Ensure options in this menu has a tick next to it. if not, click on it to put a tick there.
Now, click on your crop tool. On the top of the screen now you should see some options. Where it says width and height, you have something typed in there… delete by ressing clear on the end of this options bar…so now these boxes are blank.
Tool should now work as you want it to.
Also, when you select the crop tool, you see the crom tool apear on the option bar… you can create, delete and reset presets using the drop down button, and then clicking on the small arrow on the right hand side of the drop down box.