100K Then What?

This was my first Big Girl Purchase! 2020 Camry SE. My sister got it brand new and I bought it off of her a little over a year ago at 60K miles. I feel like it has a lot of miles on it but I keep telling myself it’s a Toyota, it will go forever. Sister made sure she took it to the dealership every time for any kind of maintenance needed. Which back then was basically oil changes and tire rotation. I took it to the dealership a couple of times for oil changes but honestly I just don’t got it like that to pay the dealership prices. I have a boyfriend that I’m able to use for my oil changes or even Havoline Xpress. But now that I’m fixing to hit 100K miles I feel like I need a real deal maintenance. Fluid flush, spark plugs.
Does anyone have any recommendations on what should be serviced at 100K miles?
Do I flush fluids? Or leave them alone?