> Which is better testing framework in terms of getting the quick results and what are main advantages of having framework in terms supporting automation?
It depends on what you want to test.
For UI E2E tests I recommend Cypress. It's the easiest one to get started with.
For other kinds of tests, I particularly like Jest, since it bundles assertions, a test runner, and tools for working with test doubles. Because Jest bundles these tools, you don't need to install and configure them yourself.
The main advantage of automating tests is described in detail in the book's first chapter, but to summarize, the more you execute them, the more time you will have saved yourself from going through functionality manually. Also, by automating them you can ensure that the test will perform the same exact steps every time, instead of relying on humans, which can often forget things or do them in different ways. I recommend you to read the book's first chapter for more details.