Keep a Journal. Think about intent/outcome logging per day, irrespective of what they ask you to do (which of course will become part of your intent) write down what YOU want to try and to that day, and do a reflection.

Make sure you respect NDA and IPR. Don't blather if there are things you know or find out which are privileged.

Don't compromise your own integrity, in a belief you "have to do it" for something which causes you qualms.

Don't be afraid to ask questions but try to avoid asking the same question twice to the same person. Caucusing is fine, but expect some "are you asking me to do your work/homework/research for you" responses sometimes.

Anyway, if that is the case I would definitely separate your work and private account.

Keeping some short notes on what you did each day is definitely a great way to reflect and think about what you have learned. Also help to create some accountability.

Are there any other interns? Get to know them. Also get to know the people you are working with. Try to pick their brains when appropriate: career advice, technical things, office politics, ...