Give Proxychains a Program, Not a Web Address
Fix proxychains exec-not-found errors by passing an executable and its arguments instead of a URL or application bundle.
proxychains4 https://example.com/ asks the wrapper to execute a web address. Give it a program followed by that program's arguments instead:
proxychains4 curl https://example.com/Choose the actual program and an authorized destination. The proxy endpoint belongs in the selected Proxychains configuration, not in the executable position. For a permitted public endpoint, the free proxy list offers candidates to enter with the protocol and fields that configuration expects.
An exec-not-found error happens before a useful proxy connection test. It does not establish proxy refusal, website blocking or DNS failure. Check that the command exists in the shell's search path, or supply its actual executable path. On macOS, an application bundle is a directory; its executable can be inside Contents/MacOS.
Successful launch is only the first requirement. The program must use networking calls proxychains-ng can intercept. A different copy already running in the background is not retroactively wrapped, and some applications pass new requests to such an existing process. Confirm which process performs the request under the intended configuration before diagnosing the resulting route.