1991 Ford f250 7.3 idi
On my way to work today my F250 decided to lose all RPM while driving, check engine light and battery light came on. Turned the ignition over twice and it finally started back up and ran smoothly, and even when I went back home after work it was fine. I don't know what caused this to happen, I'm pretty new to this so any help would be appreciated. Thank you.

 

Broken ignition switch on top of the steering column. It's difficult to kill an IDI once you get it running.

 

Check your battery cables. They should be free of corrosion and have no splits in the jacket.
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yup, this would be my first thing to look at. i have replaced at least 100 ignition switches on 87-91 trucks over the past 35 years.
you can neel it sometimes, but i drop the lower dash panels, disconnect the shift indicator, then loosen the steering column bolts and drop the column down on driver seat.
look down the top of the column with a flashlight and you will see the ignition switch. they like to separate between the plastic and metal parts.

 

Yes, especially the cheap copies. They separate easily.
OBS have been around so long, that knockoff parts are aged to the point that they appear to be original until you clean them up and have a good look. I saying this because if one unknowingly buys a new knockoff and compares it with one off truck, appearances may be deceiving.
Just because a parts store or online vendor charges a higher price, makes superior claims, or calls it OEM, does NOT mean it's the real thing.
I'm just amazed that the market for old American car parts is so large that there's even room for the chinesium producers to even tool up to make the knockoffs.