New-to-me 2015 40HP outboard: maintenance plan, impeller and fogging questions.

[Scarlett_T]

I recently bought a used 16-foot aluminum fishing boat that came with a 2015 40-horsepower outboard motor. The previous owner said it was "well-maintained," but I have no service records. I want to start fresh and establish a reliable outboard motor maintenance routine before the season starts. I plan to change the lower unit oil and spark plugs, but I'm unsure about the water pump impeller—should I replace it preventatively given the motor's age? Also, what's the best practice for fogging the engine for storage, and is there a specific fuel stabilizer you recommend for ethanol-blended gas? Any tips on checking the thermostat or anodes would also be appreciated.