How long does it take? Every student is different. You may find a module takes the full 6 months allowed. You may find it quite simple and complete everything in a matter of weeks. (The fastest is believed to be 7 weeks.)
Each module is different too. Workshops have less course work as you are assessed on your ability and skills in real situations. This has a higher value mark. On average we would expect students to complete two to four modules each year. An HE Certificate might, therefore take between two and three years to achieve. Others may take a more leisurely pace!