Reply To: Two documents side by side

To view two pages side by side,
In Design:
If you have a document with multiple pages=
Click on ‘Window’ at the top bar > click ‘Arrange’ > then ‘Split window’.
It will let you edit two pages side by side.
Photoshop:
Photoshop only allows you to open one image per window, so if you have a PDF with multiple pages, you would have to start by=
Click ‘Open’> choose a file with multiple pages (i.e. a PDF document) > click on the file you want > Open > Select the pages/images you want to open by holding down the ‘apple key'(or the windows equivalent) or hold down ‘shift’ and select the block of pages you want open > click ‘OK’> THEN…
Click on ‘Window’ at the top bar > click ‘Arrange’ > then choose the layout you want (i.e ‘2up Verticle’or ‘4-up’etc).
Important:
On photoshop, the separate windows will be saved as individual files, while on InDesign, they would be saved as the same file.
Hope this helps.