Yes! Usually you will need a sponsor to invite you to work in UK. The employers who are sponsoring you will provide a certificate of sponsorship. You need to have the required qualifications, work experience and skills for the jobs for which you have been invited to the UK through sponsorship.
The aim of providing the certificate of sponsorship is to provide support to the applications of the overseas workers. This certificate will also ensure the authorities that the employer will take all the responsibilities of the employees during their tenure of employment in the UK.