First time in Portland, advice ?

Me and my friend are planning a trip to Portland! It will be our first time on the west coast. We are flying into the Portland airport but not sure exactly where to get an Airbnb or hotel at. We plan on taking the point bus one day to cannon beach which leaves from the Portland union station. We also would like to take a tour to see mount hood which they also leave from downtown area.

Any recommendations on the best areas to stay in? How does transportation look like since we cannot rent a car?