Video of the full end to end process https://youtu.be/WBkZTJwko9w
There were issues loading the datafile due to GitHub file size restrictions. Therefore the links to download these are below
Postcode - https://osdatahub.os.uk/downloads/open/CodePointOpen
Output Areas - https://geoportal.statistics.gov.uk/datasets/31dac98df61a4312991646842b147e2f_0/explore
Census Data - https://www.nomisweb.co.uk/sources/census_2021_bulk