Can I remove keys to clean inside them?

Your system is so new no one has documented how its done clearly. Here's the only YouTube I've found that even describes the keycap at all How to get your letter keys off your 2016 MacBook Pro sadly its a bit lame. I'm not sure if the butterfly keys used in the new retina MacBook is the same or not. There are a few YouTube's that go over how they come off.

If you can pop off the keycaps without damaging them you can use a cotton swab (Q-Tip) just dampened not wet! with distilled water to clean the sugary drink off of the parts internally. The caps them selves could be dipped in a container of water and then using a paper towel and can'ed air blown dry.

If the drink got deeper into the system it could cause corrosion damage which might not show up right away, So you may want to let a pro deal with taking the system apart to correctly clean things from the other side.

Sadly Apple won't repair liquid damaged systems and its voided the warranty coverage now. Even a pro may limit you on the warranty of the repair.

I would try going to an Apple authorized service center as my first choice here. I wish you luck!