Hi Carolyn and Welcome to the forum, you might want to have a look at the following FAQ which explain where everything is
Welcome to Benefits and Work There are no trick questions when you phone and initiate the claim. You will need to have some basic information available, what you need is explained in our PIP guide
PIP help for claimants May I suggest that you favourite/bookmark this on your web browser now so that you can find it easily in future? This will allow you to return with further questions or comments about your PIP, as the claim progresses, without having to start a new topic each time. It helps us enormously when everything relating to the same claim is kept in one topic - and I hope you will find it useful too