You can take private training to get your large goods vehicle (LGV) licence and the Certificate of Professional Competence, known as a Driver CPC.
You'll also need to complete ADR training to carry dangerous goods like chemicals. ADR is the shortened name for the European Agreement on the International Carriage of Dangerous Goods by Road.
You can find LGV and ADR training providers through the Joint Approvals Unit for Periodic Training. It's recommended that you compare several providers before signing up, to see what they offer and to make sure it fits your needs.