Rose
Welcome to the forum, you might want to have a look at the following FAQ which explains where everything is
Welcome to Benefits and Work Reassessment involves a claim form, it can either be another PIP2, as you would have completed when you first claimed PIP but is more likely to be an AR1 Review form which is shorter and only ask a few questions for each activity. Completing both forms is covered in our PIP Claim guide.
www.benefitsandwork.co.uk/help-for-claimants/pip Following your returning the form there will likely be an interview or face to face (ftf / F2F), you may well have had one of these when you first applied, it won't be any different for a reassessment, the guide has sections on both the assessment and the questions you are likely to be asked,
Even if you do not have a F2F a report will be written by an assessor and sent to the DWP, it will be one of the things considered by a Decision Maker when they decide on an award.
Gordon