Kinda, it depends. You can use it when you want to describe an action (verb) you think isn't possible to do. For example: "There's no way I can help you" you can say "אין לי דרך לעזור לך". You are describing the verb to help (לעזור) But you can't say it when describing an action you simply don't want to do For example: "There is no way I'm helping you" you wouldn't use אין דרך/אין דרכים since you're emphasizing the fact you don't want to help not that you can't. In English you use "no way " for both meanings but in Hebrew it depends on the meaning. Hope it helps :)
DL rejected "No roads". But I'm sure it's possible to use it as a short answer.
I don't understand why my translation is not correct. This is the literal translation, no?
I'm no expert, but i think you should report it. דרכים, if I'm not mistaken, can mean roads, paths, or ways. But again, I am no expert.
"Path" is literally translated as "שביל" (shvil), so "no paths" would be אין שבילים if using the "strict" translation... Not sure whether "no paths" can be an acceptable translation in this specific case, as it is without context that can tell whether it has the direct meaning or a broader more general meaning...