Update README.md

Update installation Configuration Helper instructions for Python.

Author: javajason

README.md

@@ -244,9 +244,14 @@ $ docker run --rm -it -w /app -v ${PWD}:/app --entrypoint /app/src/bin/init_entr
 ```
 
 **Run With System Python**
+
+This command requires Python to already be installed on the host. If it is not, installation instructions can be found here:
+* [Install on Ubuntu](https://docs.python-guide.org/starting/install3/linux/)
+* [Install on RHEL and compatible Linux distributions](https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/9/html/installing_and_using_dynamic_programming_languages/assembly_installing-and-using-python_installing-and-using-dynamic-programming-languages)
+
 ```bash
-$ pip install PyYAML==6.0.2
-$ python /app/src/config_helper.py --generate-config
+# Run the configuration generator from the project root directory
+$ python3 src/config_helper.py --generate-config
 ```
 
 This will write 2 new files in the services/otel_collector directory: