I have a 2015 SL model with 96k miles. I feel that it is becoming a bit sluggish.
Any recommendations on what type if maintenance it would need?
Check the recommended plug change interval in the manual. Some OEM plugs are 60-100k, some are like 30k. Not sure what ignition a 2015 has, but new plugs, cap, rotor and wires is about $100-$150 and an afternoon. If your plugs are worn out, it can make a big difference. Check the air filter and fuel filter, all of that stuff can impact performance. Or take it to a good independent mechanic (or the dealer if you trust them) and have them give it a going over. 100k is when a lot of stuff is due or overdue. And check the manual for things like timing belt service (some engines have chains, but belts need replacing and often that's a major service, hoses, water pump, belts, belt tensioner, radiator flush - all the stuff you have to remove to get to the timing belt is replaced, and can keep you from being stranded or having an expensive breakdown).
The dealer's gonna recommend and expensive fuel system flush, an experienced indie mechanic who wants your business will tell you if that's needed or not.
Cvt fluid change if not done yet
I totally agree
Did you not get the owners manual with the vehicle?
If so, follow the manual, not the dealership's, schedule. If not, get a manual.
Picking up a used vehicle without a file folder of all maintenance receipts means you just have to start: look at all fluids both colour and level. Look at all belts and hoses for signs of wear. Etc.