Ok well thats one way to show you have little information about what you are talking about.
Ron Paul hasnt been on a presidential ticket since the 80s.... If we want most popular/famous I'd look to the presidential candidates they put forwrd as that represents the accepted norm of the whole of the party (Ron as a senator only represents the views of a small district).
So Jo Jorgenson or Gary Johnson would be the two most recent and most modern representatives of the party.
Neither look very similar to the GOP in their views.
As to answer your question and how Jo and Libertarians as a whole tend to differ fromt he GOP well here are some examples of that (some are Jo's policies and the parties:
* Jo was for more open borders, wanting to remove immigration quotas reregulate the borders to allow immigrants easier access to come here.
* Jo and most libertarians are adamatly against Trump's border wall
* Jo opposes the war on drug
Just a few examples off the cuff.