how do i

i need help when ever i make a coaster go beyond vertical it twists the other way so it stops me from going beyond vertical for example i wanna make a eurofighter with a beyond vertical drop it wont work

The first and last vertex are acting as a roll node, too. You can enter the corresponding menu via ctrl leftlick and change the roll angle to the value you need.

for future reference, there is an Official Ask Thread for short questions like this that don't generally require starting a new thread