Hello @Voynova, Silvena,
welcome to this moderated Azure community forum.
Yes, you can have multiple Azure Function being executed within the same Web App.
These functions with share the resources but that is ok.
Only when you want to split your Azure Solution in multiple VNETs it's probably recommended to split the ingest (The IoT Hub logic) with the processing stuff (output of ADT).
Here is a GitHub example with multiple functions for processing Azure Digital Twins logic.
See how multiple functions are put in multiple files although this could have been one big file technically (but that is not practical).
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