The check gauges light has been coming on in my 2006 Ford F350 superduty, I have the 6.0 powerstroke turbo diesel. Sitting idel it's bottomed out, when you start driving it comes back up then loses it again... whats going on and how can I fix this??

If warning lights (e.g. battery, ABS, SRS, or others) start appearing in concert with one another on the dash, immediately suspect the alternator.

Here's how to easily test your charging system:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-10.html#post1973613

The title to your question is about oil pressure, so I'm not sure if what I gave you is relevant. The picture is not real clear. If not, the diesel engine troublshooting link below may help:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-8.html#post1415281

Ensure oil and filter have been recently changed and the oil comes to the "FULL" level. Verify oil pressure with a known good mechanical gauge. Oil pressure may be too low. The cutoff will shut the engine down when the oil pressure is too low.