First question is it possible for tectonic plates to meet at the poles?
Absolutely. The Gakkel Ridge is an active divergent boundary on today's earth. A convergent boundary doesn't exist today (but they are close, e.g. Aleutan trench !), but there's no reason that it couldn't exist at all through a planet's history, if there are plate tectonics on such a planet.
Second question if volcanic activity is present can this alter the climate?
Depends. Huge single eruptions a la Tambora or even Toba will likely cause short time cooling ("volcanic winter"). But really huge basalt flows ("flood basalts") can release so much greenhouse gases that thawing starts over a longer period. This is one of the hypotheses' for helping an earth-like planet out of a snow- or slushball state ;-)
If so at what degree? Would it just melt some snow around or it could create a microclime that can allow people and animals and plants to live there?
Local melting from lave flows or albedo change by dark ash cover can have an influence, but as soon as the cover is gone and the lava has cooled climatic conditions will return to status ante. Volcanic winters also don't last long (some say their influence is overestimated, but that's boring science). Make it a nice flood basalt à la Dekkan traps, huge CO2 release and no Himalaya sized mountain ranges that could cool via weathering.
So, tl;dr: Yes, tectonic activity doesn't stop at the poles. Impact of volcanic events depend on size and timeline, up to planetary effects over the course of a few million years. But as this is world-building, anything can happen :-)