What do I do if my instamax mini 8 has all the setting lights flashing and the red light on the viewfinder on?

look at owners manual

Hi. Based on your brief description of the problem I would think that the camera is failing to focus and the flashing red light in the viewfinder is the auto-focus indicator, make sure that the red auto-focus indicator is positioned in the centre of the viewfinder initially until you have experience of using it (to do this consult your camera manual) focus on a subject that has some contrast ie a red brick wall, grass or pebbles on a beach.

hi there.
not sure if this link will help you out but have a look.
My instax mini 8 won turn on Google Search

You need to change the battery that powers the internal clock and holds your settings.  The slot is on the underside of the grip.

A few things to try, based on my FG's operation: - The most obvious- are your batteries good? Correct type? If they are: - When all is well the red LED metering lights will appear in the viewfinder window on the right side, in the range of shutter speed numbers. - The red LED metering lights are only activated when you press the shutter release button (halfway). The lights go out after a few seconds if the shutter button is not held down. Just tap the shutter button to reactivate them. - The shutter speed setting dial must NOT be on B (Bulb) or M90 (non-electronic Manual mode) if you want to see the red LED metering lights. The lights do not operate on these two settings because metering is irrelevant here (you'd be doing the metering, not the camera). - If you're in P (Program mode) the lens aperture must be set all the way to the smallest setting (usually f22 or f16, depending on the lens). If not, you'll only see blinking lights at the top and bottom of the shutter speed range on the right in the viewfinder. That's a reminder to set the lens to the smallest (highest numeric) aperture.
Hope these help. The FG is a great little camera.

Seems like your problem on greyish/blurry viewfinder is caused by the camera getting water logged. Get your cam cleaned by Nikon.

The flashing red light usually happens if you have this indicator set in the camera. This may not necessarily be an error.. just a setting that you have put in place in your menu.

Hi . .  I downloaded the manual . . found I needed to replace the 3 volt lithium battery located on the underside of the hand grip for the zoom. Changed the battery . . . No red flashing icon in the viewfinder.
Cheers
Steve

The flashing "boat" in the middle of the viewfinder just means the button battery is dead. Camera will still work. It's the little pull-out light grey plastic thing that's next to the heel of your right hand when you're using the camera normally. You need a CR2025 cell.

ive gt to use it recently and it woot the canovision E100,hardly been used i went to use it and it wouldnt come on , there is a red light