how to earn through posting threads in a forum?

As i noticed many people engaging in posting threads and replying. Bt i dont know how we can earn through posting those things? Or where can we find our earnings through it..so plz frens help me...:(

Assalam-O-Alaikum ye kam bohat he asan hey key ap is pakistan forex forum me jab posting kartey hen to ap ko is ka bonus milta hey jis sey ap real trading kartey hen aur real money earn kartey hen.