Completing a custom field depending on four other custom fields using automation

[Jenny Smedley]

Hello, I would like to identify "external use cases" for my team using logic derived from four other custom fields.  So I would like "External Use Cases" to be yes if 

Work Type = Customer Proposition or

Work Type = Optimisation or

Work Type = Scaling and if

Label = DP_external_request

Can you help please?

[Jenny Smedley]

Thanks to the amazing laiseng.liew@gousto.co.uk, we worked out how to do this using branch automation which I didn't know existed