A typical railroad (road) has a certain angle of inclination to counter centrifugal forces on curves, which is called a “cant” (or “bank”).
There is currently no plugin I have found on Roblox that can reproduce these.
***However, the plugin that creates roller coasters can create banks, but cannot use original rails.
One idea I had was to use a plug-in such as Archimedes to bend the rails with a pre-sloped angle (the approach section is gradually tilted using wedge parts on one side of the rails). But if you have any other good ideas, please let me know.