Is lava produced at a continent-oceanic convergent boundary, if so how?
Yes, through a process called subduction
When oceanic crust converges with a continental crust, the oceanic plate will fall underneath the continental plate, like so:
This process is called subduction. Areas around subduction are called subduction zones. As the oceanic plate sinks deeper and deeper underneath the continental plate, the pressure and temperature rise dramatically - melting the crust above it and releasing magma up towards the surface.