We are going to model a a deformable alumium can filled with high-pressure gas. Steady state. Can fluent deal with this case? or maybe we need to try some FEM software like Abacus?

Fluent at the moment doesn't include the capability to do FSI (Fluid-Structure Interaction) analysis. But for your case I doubt that this is what you need. You'll have only a constant pressure in your can, perhaps decreasing slightly with the deformations. Anyway, any structural analysis tool should offer the capability to simulate pressure vessels.

Good luck

George