Questions about example sentences with, and the definition and usage of "Activites"

A: First of all, I'm going to talk to you about activities that YOU CAN DO WHILE YOU'RE AT Disneyland.

A: it would sound more natural if you said: i need to run some errands

A: The thought is somewhat there but I don't really understand. Maybe if "and" instead of "however" was used, it'd make more sense.

I organized some Korea fan activities and helped as a volunteer for Korean events.