Spotlight makes it easy to find anything on your Mac, including text inside of all common file formats. macOS offers Spotlight for direct searching in two distinct ways: via the Spotlight item in the menu bar or pressing Command-spacebar, and in the Finder in a Search field or pressing Command-Option-spacebar.
Both kinds of search will yield a similar set of results, but not identical ones. Both kinds of searches show you matching file and folder names, email messages and documents that include the search text, and other metadata matches.