1997 f150xl 4.6

Driving home Saturday night my check engine light is flashing. Can feel loss of power.
Scan code at oreilly today comes up as P0307 misfire cylinder 7.
I'm already aware it's most likely my spark plugs or coils, or both...
Can I pull just the number 7 spark plug and replace it or do k need to replace all 8? I would like to do this step by step because I plan on getting rid of this truck in a few months, put $400 into it last month replacing a broken coolant pipe. Can't afford anything right now really.
Advice??

 

I'd change only what's needed but would also be honest with buyers so they're aware plugs will need changing soon.

Pull the boot & plug--visual inspection should show if one or both is at fault. They'd cost about $12 or so to replace together. If they're fine then its the the COP which can probably be found for $50 or so most anywhere.

HTH