Most schools have gear available for the training process and its use is included in the cost of your P2 training course. If not, it is wise to carefully consider what gear will be best suited for your initial beginner skill level as well as what kind of flying you intend to do.
Almost all paragliding wing manufacturers make several quality beginner level gliders. Current options that any instructor would recommend include: Ozone, Gin, Nova, Advance, Skywalk, Niviuk, and the list goes on. Talk with your instructor about gear purchase options, if you are limited to a certain budget there is a good chance that decent used gear can be found.
Everything you need for your training will be provided, so don't feel obligated to get anything ahead of time.
***The best instructors give you all the tools, skills, tricks, and every last bit of helpful information they can. Be wary of any instructor that claims one way is best or one piece of gear is best.***