I have created an extended backoffice dashboard(using angular and .NET). Now im creating the front end of the project which is another phase of the project. MVCs and APIs will be used to link the dB to the frontend. Whats the best language practice to use for frontend to link the html with the MVCs? Any ideas would be helpful. Thanks

Really depends on what you want… Or how you’ve already constructed your APIs. Old trusted REST when you want to stateless or gRPC when you need stateful connections. It really depends on what you’re doing and what you want to achieve.

How this is worded seems a little odd. It sounds like you are using Umbraco but then not really using Umbraco. Have you not built your solution using Umbraco backoffice, document types, nodes etc?