Hi Parth,
1. No it's not required in all your projects, however each process group should be covered at least once in your total experience. As stated on page 6 of the PMI handbook - "You should have experience in all five process groups across all your project management experience submitted on the application. However, on a single project, you do not need to have experience in all five process groups."
2. Depends. A project has the following characteristics:
- A project is time limited (it has a definite beginning and an end)
- A project is unique
- A project is undertake for a purpose (it will yield a specific product, service or result)
If you think each of those phases matches all the criteria given above, then you can classify each of those phases as a separate project. Otherwise you can club it as a single project and provide the appropriate description.
Hope this helps.