...The details of how this is done depend on the editor or plugin that you are using to communicate with python-lsp-server. The configuration options are available at that level are documented in CONFIGURATION.md. Overall configuration is computed first from user configuration (in home directory), overridden by configuration passed in by the language client, and then overridden by configuration discovered in the workspace.
clangd understands your C++ code and adds smart features to your editor: code completion, compile errors, definition, and more. clangd is a language server that can work with many editors via a plugin. Here’s Visual Studio Code with the clangd plugin, demonstrating code completion.