You can find apprenticeships in different ways:

The Government's 'Find an apprenticeship' service is the main way to search for a degree apprenticeship. This lists all available apprenticeships at all levels.
GOV.UK also publishes a separate list of higher and degree apprenticeship vacancies.
Other resources
You can also search for apprenticeships in other ways:

UCAS publish a list of degree apprenticeship jobs.

Prospects also provide a searchable listing of degree apprenticeships.

The 'Rate My Apprenticeship' website publishes a list of the top 100 employers of apprenticeships rated by school and college leavers.

The Amazing Apprenticeships site includes a 'Vacancy snapshot'.
5. Employers and providers
Specific employers will also advertise apprenticeship opportunities, including through many of the well-known jobs websites and through their own websites. Many will also advertise at jobs fairs.
You can also look at the websites of universities and colleges to see what kind of programmes they run and who they partner with.