Best places to go to Bangkok and Phuket

Hello Internations guys in Bangkok!

My best friend and I are travelling to bangkok and Phuket on Jan Protected content .
This will be our first time there and since we are on time constraint we want to go to the best places in Bangkok. We will stay there for 2 nights then travel to Phuket on 12 of Jan.
Can you please give us suggestion? Any one wanted to meet for a coffee on that date?

Thank you