Blinking check engine light

Lol helps greatly. Sensory overload! Makes me think I might drop off to mechanic so I don't start the costly process of changing parts. I bought with 169000 and I have 174000 on the odometer now. No idea when plugs were replaced or if any cops have been changed out. Since its at full throttle what do you think about fuel filter as a first step? I guess I could pull a plug out and look at the general condition. I've watched the videos about using carb cleaner to dissolve carbon on plugs first but still scares me

Thinking further about when lights went off the truck didn't seem to have quite the power as normal which I guess could be starving for fuel or a cylinder dropping out.