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No. Promoting a post puts the post into a queue of Sponsored posts that rotate through the Ecency feed and it gives the post an opportunity for more people to see it. You can see the current queue
www ecency.com/promoted

If you want to use Points, send them as a gift to your friend so that he can use boost+ and purchase a 200HP delegation from Ecency.

Nope..
Promote means the post you select for promotion will appears randomly on feed of other users (even if you are not following list).

It increases the probability that people will upvote posts by that user because more people will see that post for longer.

Thanks for the replies. It's clarifying.