I am trying to clear up space to see if I will be able to download apps without "error code...."&"insufficient...." messages and get rid of the running out of storage or low on storage icons.
Welcome to Android Central! What device do you have? Moving apps to SD depends on the device you have and the apps you're trying to move. Not all phones can do this, and if you can, not all apps support it. When you move an app, you're only moving a portion of the app to SD--a substantial portion of the app remains behind in Internal Storage. If you wanted to move the whole app, you'd probably have to root your device.