Your solicitor will explain everything to you, just remember to ask them anything you’re unsure about.
Solicitors are there to make sure your purchase goes through legally and accurately for you. They will go through a process called conveyancing to make sure there are no nasty surprises in your lease or for your property, such as flood risks or chancel repair liabilities (an ancient law that relates to maintaining the nearby church!).
They will also be responsible for transferring the money on the big day.