First of all congratulations! It’s the most ideal google search while being on a job hunt. While a telephonic conversation confirms your acceptance of a job offer writing an acceptance letter is the best formal way to say yes.
An Interview can make or break the chances of you securing the job offer and its not everyday that we get to be interviewed for our dream job. But chances are if you are here watching this video then you are one of those lucky candidates who has got this opportunity.