This certainly is strange! I do see you're zoomed out to .03% which is insane zoom! Can you click the place in the lower left of your screen, where it says .03% and change your view from there? It looks like you clicked Option+Command 0, or hit View>Fit All In Window. Changing your zoom in the View menu, or using that widget at the bottom should move you to normal view.
This looks like it might have been a page on which you'd maybe placed a bunch of elements and either didn't resize them down, or somehow got rid of the resizing. Another way they could have gone in at that size, is if you used drag and drop, instead of File>Place to get them on an artboard. On this screen I can only make out 3 artboards that are not aligned with each other. Is this the same amount of artboards that show in your Window>Artboards panel, or are others hidden from view?
If this was what my screen looked like, I'd do my best to move and approximately resize whatever I needed to fit on any of my existing artboards (I'd even stack a bunch of things into ONE artboard, and then distribute them to new artboards that have the settings I want). Then, I'd likely use the Artboards tool with Shift to select multiples of the existing artboards, and then use the alignment options in my control bar (or Window>Align) to arrange the artboards and separate them out as needed - also resizing them to the dimensions I want. If I THEN needed more artboards, I'd make them and move my assets into them. With so many things on here, it may also help to rename the appropriate layers and sublayers, so you know what's on each. Layer management is SO helpful here, especially when organizing things. I'm a big fan of the selection column, for moving things among layers. If you want to learn more about those, check out https://helpx.adobe.com/illustrator/using/layers.html It would take some work, but then you can see everything on there, and not have to be sooooo very zoomed out - and you wouldn't have to start from scratch, and reimport everything. Of course, that's also an option, if you prefer. .
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