You don’t need a simulator. Follow these guidelines:
All button operated Garmins (400, 420, 430, 530, 1000) have the same interface. Holding CLR takes you back to the main navigation page if you get lost. Pressing CLR once you’re there cycles you through detail levels (full, -1, -2, -3).
Information displayed is organized in chapters and pages and the combination button on the lower right is used for navigation and selection. Big knob is chapter, small knob is page. Press the button for the cursor. When the cursor is activated, the big knob becomes the X axis and the small knob becomes the Y axis, even for text, though I think of the Y axis like the wheels on a mechanical odometer for scrolling through the values. (Or the big knob as left/right arrow keys and the small knob as up/down — from a human factors perspective, the rotary encoder is faster than having to press a button a bunch of times, but less intuitive).
Last chapter is always “nearest” and the first page of that is airport, so if you lose your engine, crank big knob to the right and little knob to the left and you get your nearest airports. Later pages can identify the nearest ATC facility, etc). Pressing “ENT” on a frequency loads it into the standby position on coms.
The most confusing thing is knowing that pressing “ENT” is for selection and pressing the button on the combination knob is to activate/deactivate the cursor.
I like to use the OBS on the HSI to give me an extended centerline to aid with pattern entry.