As far as I'm aware, there's no direct facility for it. You need to set up a group for them, so they can play *as* a group (so they'll be playing vote chess as normal, just the same as you are, except theirs will be a team with only one person in it).
how challenge an individual master i voteches?

So it is not possible to do what chess.com announce about votechess???
quote:
Vote Chess!
Play Team vs. Team or Against a Master!
You get to cast your vote on what is the very best move as you play chess against a strong individual or another team of chess players!

If the master is willing to create his own private vote chess group just for the purpose, it's doable. That's why step 1 is so important.
I am running a votechess team, The Voters, how is it possible for my team to sent a challenge to a single player...a team against an individual player?
Chess.com write you can...but how?
Vote Chess!
Play Team vs. Team or Against a Master!
You get to cast your vote on what is the very best move as you play chess against a strong individual or another team of chess players!
View Vote Leaderboard
View Open Team Vote Chess Seeks
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