You can use pkg.go.dev to search for packages and for symbols in packages. Follow the suggestions below to discover what you're looking for.
Searching by package
You can search for packages in which the search text occurs in the package name, package path, synopsis, or README.
Results are grouped by module, displaying the most relevant package in each module.
You can also search for a package by its full or partial import path.
If the package path you specified is complete enough, matching a full package import path, you will be brought directly to the details page for the latest version of that package.
Searching by symbol
You can also search for a symbol by name across all packages. A symbol is a constant, variable, function, type, field, or method.
Searching by symbol will return a list of packages containing the symbol you specify. You can search by the following: