Hi Pooja,
Your query shows your enthusiasm for the new job.
As an HR Exec... I am not sure what exactly your profile is. But what I generally understand, it would be mainly recruitment and all the activities around it, i.e., maybe induction, exits, career planning of the new joinee, etc.
In the induction, you must have received enough information about the organization, its working, culture, values, how did it start, its growth, the management team, board of directors, board of advisors.
If you are in recruitment, then try to gather as much info about the company as possible. This will help you to answer the candidate's queries fluently and confidently. Learn the strong points about which you can talk easily to sell your company to the prospective candidate. Also, know the weaknesses for your information, so you do not promise anything to the candidate which you can't fulfill at a later stage.
If you have the permission to discuss the offer with the candidate, then understand the offer letter and the salary break-up of your org thoroughly so you don't have to go back and forth much with the candidate.
In your enthusiasm to start soon on your new job... don't just jump into it, but understand your profile well so you know what is expected of you, and if need be, spend a couple of days with your senior/reporting manager to understand the working of the org properly.
Whatever you do, always be optimistic and positive; this will take you places.
I hope this answers your query.
All the best,
Rupa.