If you are more interested in the engineering side—how actual file search engines like (which powers Elasticsearch and Solr) work—the architecture is based on this seminal work:
.sql or .bak files containing user credentials, personal identifiable information (PII), and financial data. index of files
If you need a simple .txt or Excel-compatible list of every file in a specific folder, use the Command Prompt. Open the folder you want to index. If you are more interested in the engineering