The article provides an in-depth tutorial on using the pytest framework to execute multiple Selenium test cases from a single file, focusing on scenarios where selective execution is needed. It explains how to create a pytest project, run tests from single or multiple files, and employ custom markers and substring expressions to execute specific subsets of tests. The tutorial includes practical examples of Selenium test scripts for the LambdaTest ToDoApp and Google search, illustrating the usage of Chrome WebDriver and highlighting the importance of proper test naming conventions. Additionally, it emphasizes the need for registering custom markers in the pytest.ini file to avoid execution errors and offers insights into grouping tests by substring matching. The article is aimed at both beginners and professionals looking to enhance their expertise in Selenium automation testing with Python, providing a comprehensive guide to managing and executing test cases efficiently using pytest.