Two plates colliding and one being pushed upwards is called subduction.
When two plates collide, compression pushes the crust upwards, thus creating a mountain range.
CONVECTION
When one tectonic plate presses into another it can either force it upwards or downwards. If it is upwards, then mountains are formed as the plate pushes up the surface of the earth above it.
When two plates collide one pushes the other one down. Then the magma goes through the gaps between the plates and then the volcano erupts. Volcanoes can also erupt by the plates spreading apart.
When plates move apart or diverge, it is called a normal fault (happens along a divergent boundary). When plates collide or converge, a reverse fault occurs (when the hanging wall pushes up, and the foot wall pushes down). When plates slide past each other, it is called a strike-slip fault, which typically occurs at a transform plate boundary.Also, if you are still having doubts, do more research on strike-slip faults, normal faults, and reverse faults by just typing it in.
Convergent Boundary
Mountains form where continental and oceanic plates collide by the actions of the plates upon one another. Often one plate pushes up and over the other one, and the upper one creates a row of mountains.
Subduction is one of several things that can occur when two tectonic plates collide. In subduction, one plate ends up dropping below the other plate (think of a wrestler dropping low to get under his opponent's guard). As the one plate drops lower, it pushes the other plate upwards, often causing a mountain chain to form.
There are plates that are always shifting around in the ground. They move 1cm every day. When the plates collide,they make a big BOOM which cause the things in the volcano to heat up. Then the heat pushes everything to the opening in the volcano which causes it to erupt and shoot out.
Faults themselves don't move; they're cracks in between tectonic plates which do the moving. The plates move due to slow-moving convection currents underneath. It's basically slowly circulating magma that slowly pushes the plates along. As plates slide and collide with each other, they change the shape and position of the faults in between.
I pushes the warm air upwards.
The way tectonic plates move is by the heat from the core that goes up to the mantle which pushes up the rock and pushes them together to form tectonic plates. Later the tectonic plates slowly go back down until the heat of the core reaches the mantle once again.