I will design case study,ux documentation,research,user flow,user personas etc

What is a user persona? A user persona is a fictional representation of your ideal customer. As a UX designer, you'll start the design process by conducting user research—building empathy with your target users and identifying exactly what they need from the product you're designing.

Having a proper design cycle, where the users are taken in account, investigated and understood, where the concepts and prototypes are created based on understanding the users - we ensure a more better experience and in a e-commerce world, everything that is annoying or not understandable.

The short answer is: It depends. There isn't really a magic number a brand or project should follow, but it is generally recognized that 3-8 personas are sufficient in most cases. Many people, including design professionals, are often confused about the differences between customer segment personas.

Personas are fictional characters, which you create based upon your research in order to represent the different user types that might use your service, product, site, or brand in a similar way. Creating personas will help you to understand your users' needs, experiences, behaviors and goals.