Update PreperationNewCourses.md

src/instructors/PreperationNewCourses.md

@@ -103,7 +103,7 @@ Add new Notebooks and fill them with content to your wishes.
 ### 5. Collect Python requirements
 
 Depending on the contents of the Jupyter Notebook, additional third-party Python packages might be required.
-Usually these external dependencies are collected in a `requirements.txt` or `environement.yml` file:
+Usually these external dependencies are collected in a `requirements.txt` or `environment.yml` file:
 
 Please have a look at the following links for further information: