can you give me the exact address of $HT or whatever the netowrk tolken is to buy the HECO coins? there are so many of them.  I have the HECO network added to my metamask and I have the custom coins I want to buy added to the HECO network in the metmask.  how do I buy them? where do I buy the $HT coins and with what coin, BNB? this is where I am confused. I am not new to trading, but these new networks are confusing me thank you!