I customized a command to display a UI which using Stop(). After the player clicks, I want to continue to run the next line from the line where the Naninovelscript stops. What function should I use?

There is no built-in way to jump to a non-labelled point with goto. Check the VariableInputUI script for reference on how to resume playback from the next line, however with @input you are meant to use @stop in naniscript instead of Stop() which allows for better control via naniscript.