can someone???

I think it can like teleport her wherever so she can make a quick escape? I'm not entirely sure either but thats the vibe I'm getting

I think it means at the end of the 6 months when shes gonna die she gets to use it to go any place she wants before her death

From what I understand he is basically giving her the opportunity to choose where she will die after the 6 months have passed

It's a potion that grants her the ability to teleport once wherever she'd like. She can use it whenever she wants but yeah, as the previous comments state, he suggested her to use it right before she dies. I could imagine her using it to save the Duke if he gets in trouble though o -o

So in Six months she is gonna die and the red bottle will take her anywhere she wants to go to die, somewhere nice/pretty or something

Yeah, unless she uses the bottle before that, it's not restricted to just before she dies, she can use it at any point