Discuss how to grow up a forum...

I have a forum powered by phpBB,but I don't know how to develop it.I live in China,there is no students or friends have interests in common for me.I like games,so I want to tend ittoSimulation post mods and discuss it forum.Because I have bought it on steam.I tried published the forum to social like Facebook group/Vk group,but they don't like it,therefore they delete this post......I don't know how to do it successfully.

Which its the best ideas toattractpeople into my forum?:/