going to Hong Kong Museum of History whampoa garden and fisherman's Wharf

Yes, you can cover these three places just in one day. Follow the route below:
The hotel is about 0.7 miles distance from the museum, you can cover the distance by walking, and that may takes about 15-20 mins. Or walk to the nearby Ping Chi Street Hung Hom to take the bus 5A to Hung Hom Railway Station. Then walk about 440 yards to the museum. The bus fare is HKD4.3 and the duration is about 5 mins.

Well, the museum is very near the garden, about 1.2 miles. YOu can walk to HK Polytechnic University to take the bus No, 8A to Whampoa Garden directly. The bus fare is HKD4.3 and the duration is about 20 mins.
After the sightseeing in the garden, you can head to the China Ferry Terminal to take the ferry to Macau. Walk to Tak Man Street to take the bus No. 6a to Canton Road. Then walk for 80 yards, you will reach the ferry terminal. The fare is HKD6.2 and the duration is about 20 mins.

You will arrive at Maritime Ferry Terminal, which is about 720 yards walking distance from fisherman’s wharf.

Before your check-in to the hotel, I suggest you go to Mong KOk for a simple shopping, or you can go to Tsim Sha Tsui for lunch and visit the Avenues of Stars.

Dear Chat and Lily, I heard the Avenue of Stars will be closed after Sep. Please clarify that.

is it really closed? will be arriving in HK on sept21,2015 i hope theyre open

I heard it will be closed on 8th October. If you travel before that, you will have a chance to travel there.