Your question isn't specific enough right now. The global and local planners built-in to the navigation stack already have multiple modes, depending on the obstacles encountered. There are also nodes that support state machines, such as smach. Can you be more specific?

Sorry what I actually ment was how do I switch to different modes depending on my need like a mode for single lane driving and multi lane driving, I'd just like to know how to switch @mark rose

That's a good question. I don't know if there are existing projects that plug in to the global and local planner interfaces to address the problem of car navigation. The global/local framework is still a good model, I think, but you might need entirely custom planner plugins.

You might look at this earlier question and also the Ackerman ROS group.