On the Remix-Solidity IDE, select the Web3 Provider under the Environment under the run option, and the prompt that cannot connect to the test network Ganache appears.

Solution: Usually, the browser IDE you use is: https://ethereum.github.io/browser-solidity. If there is a prompt that you cannot connect to the Ganache test network, you can use another browser IDE: http://ethereum.github.io/browser-solidity ://remix.ethereum.org will do.