Big image

If you embed a big image like this one that is 2448 X 3264 pixels into a Google site it may be rotated.
You should resize it to a more reasonable size before uploading it.

If you don't have an image editor try

Full size - so big that GS rotates it

Reduced to about 300 px wide before uploading it

Inserted from Drive

I am old enough to remember the early days of the Internet when broadband was rare. Most people had slow dialup. Also computer speeds were much slower. 

If an image that had a large file size was inserted in a web page it would take the viewer many minutes to download and view it so inserting big images was highly discouraged.

Today most of us have better speeds but it is still better to reduce image file sizes before inserting them into web sites in order to increase page speed and to reduce using up your web space allocation.