Design pattern for web api consumption

I'm starting a new personal project which will be a .net core web api back-end with a react front-end UI.

The back-end will query an existing database with a lot of endpoints. But I will also build a DB on my own for additional features.

Is there a design pattern or architectural pattern that can handle the existing database part?

Here is what I thought of:

• Consuming a web API using a typed HttpClient — .NET Core (should I build a generic service agent or one for each endpoint type )
• A factory to build the correct request with the right parameters
• A bridge to handle all the endpoints types and verb(GET/POST/...)

Any suggestions are welcome!