uploaded images too big

I'm just starting building my website on squarespace. When I upload images, they are automatically cropped, showing only a small part of the image. I just want the whole image, not a cropped section that takes up the whole page. 

Can you provide a little more detail? Where are you uploading the images? Image blocks? Galleries? Section backgrounds?

If this is about image blocks, then you can toggle between the image filling the block and fitting within the block.

If this is about gallery sections, there are different ways to set these up that will effect whether they get cropped or not.

If this is about background image then these are always going to be cropped to some extent as they need to fill the allocated space behind the content.

Maybe you mean the way the uploaded images are displayed in the content library? This is indeed a crazy way of displaying them that Squarespace has come up with.  But don't worry, the images are not cropped, it just looks like that in the content library.

Example: