new here!

[rpmraper]

quick question. i have a 2012 dongfang rtc. it in " ok" condition. still stuff to work on. i noticed a line im assuming is a fuel line. its on a nipple at the bottom of the gas tank. i fount it just hanging there. i know it goes to something because i can see on the rubber where there used to be a clamp on it. i have no idea where this goes. also , i have a vac port on my intake from the carb to the block that had a block off cap on it. just wondering if anyone can shed light on this subject? im used to honda fuel injection so this is all new to me. thanks for help in advance and ride safe!

[rpmraper]

can someone just look under the bike and tell me where the hose from the tank goes to please.