Ok, ACP - Permissions - Forum Permissions. Select the forum(s) you want people to be able to make polls in, and you will see a little dropdown box for every group (Administrators, Registered Users etc). Simply select "Full Access" for administrators, and "Standard Access + Polls" for everyone else, if you want them to be able to make polls. Polls in phpBB3 are actually in the new topic page, so click "New Topic" in the forums you just changed, and at the bottom there should be "Poll Creation". Create the poll there.
Edit: Apologies cherokee red, it didn't notify that a new post had been made.
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