Can somebody tell me how to post a video here???

I made a mike video long ago. An earth song video. And I already পোষ্ট হয়েছে it on YouTube but I wanna post it here on ফ্যানপপ too. Every time I try, it's just so confusing. I have no idea what they want me to do. I just need to know how to post a video from my computer and one from YouTube (if that's possible) So how in the world do I do so?