In order to list local conan packages, run
conan search
Example output:
$ conan search Existing package recipes: cpr/1.6.2 elasticlient/0.2 elasticlient/0.2@demo/testing gtest/cci.20210126 jsoncpp/1.9.4 libcurl/7.69.1 libcurl/7.78.0 openssl/1.1.1l zlib/1.2.11