Swanseaone
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 I would start by having a look at our PIP Claim guide, this explains how to make your claim and has an explanation of the criteria that you will need to meet for an award.
PIP is very different from DLA, it's not a question of showing that you conditions are worse it's just different criteria.
If you have any questions then please reply to my post and we will do our best to help.
Gordon