Market Rules Explanation

Market Rules wrote:1. Forum User [Player] is allowed to create one (1) thread per account, with option to edit their own topic name x amount of times they wish at any point, or message any member of staff to request the thread name to be changed.

Based on this rule, players are only allowed to create one topic each market section. So at this moment, I have a thread in the "Selling" section and and "Trading" section. Am I allowed to create another thread/topic in the "Buying" section too?

Yes.
You are allowed to post in the Selling and Trading and Buying thread.
E.g. Not allowed to made 2 threads in 1 subsection.
I will update this now to make it more clearer.

I got another question, though it's not about market rules. According to this rule,

Game Rules wrote:12. If you beg a staff member for items, you will be warned to stop. If you continue to beg, you will be muted for 1 hour. Same goes for events. If you still continue after that, the mute will be extended. Same applies to begging players for items.

you can be muted if begging staffs for items and events. Is it also punishable to beg players for items? Cuz an ambassador (whose name I will not mention) told me that you won't get punished for begging other players for items. Example below:

It is against the rules. As clearly stated in the quote which you bolded out.