I recently purchased D750 and also a first time user of Nikon. I am really struggling to use the body with all the settings.
My recent two key challenges has been -
1. AFOCUS not making the beep sound or have any green indicator in the view finder hence i am failing to figure out if i have locked focus correctly.
2. While i shoot in "Manual" mode - the camera changes either the aperture or shutter speed by itself when i choose an ISO.
Please note i am using the body with Nikon 85mm prime, f1.4 and my auto focus button is at the back and not the shutter.
Also if the answers is there in the manual, Kindly refer me to the page. I have read Autofocus section multiple times.