Hi Sumit,
First, welcome to UiPath Community!
In my opinion the best way to start learning how to use UiPath Platform is to enroll in Academy courses:
You can download the free Community Edition from UiPath website:
https://www.uipath.com/community-edition-download
You can find the user guides in this post:
And you can find a lot of useful posts in the Forum. Search what you need and if you don’t get any results you can post a question.
Happy learning!