How to set zoom and flip images in IrfanView?

Question

Images

A good program in terms of file opening speed (compared to standard programs in Windows).

The only thing I did not find:
1. How to scale the image only with the mouse wheel, without holding down the Ctrl key.
2. How to navigate through the images in a folder using only the arrow keys, without the mouse wheel.

Can someone suggest how to do this?
Googling did not give adequate results.