To receive process level metrics use our /timeseries API and choose one of the pgi (Process) related timeseries, such as 'com.dynatrace.builtin:pgi.cpu.usage'.
You can find some more documentation within our help system:
Here you can get process group list:
Here you will get process list:
Here in tineseries api you have list of available metrics.
Then you can use time series api to send entities and metrics you need to Dynatrace server and you should get results.