1. what zodiac constellations is the sun going into at the start of our summer?

The correct answer to this open question is the following.

The zodiac constellations are the sun going into the start of our summer are the zodiac constellations of Sagittarius and Scorpius.  

From the month of June to September, it is a good period to watch the night sky and see the constellations. Not only you can see those zodiac constellations but also the constellations of Lyra, Hercules, Cygnus, Aquila, and Ophiuchus.

But if you miss it, the following are constellations that can be observed at any time of the year: Ursa Major, Ursa Minor, Cassiopea, Draco, and Cepheus.