All 3D has been created in Nomad, and edited/layout in Autodesk Sketchbook Pro and Procreate
What course are you applying for? That will define what sort of work you present, how it should be presented and what software you should start familiarising yourself with.
You definitely have the creative skills needed but can’t hurt to go that extra mile bulking up your portfolio. You obviously have a love of monsters and creatures (don’t we all!) I’d suggest working up some stuff outside of your comfort zone to show versatility, real world stuff, photorealistic objects, anatomy studies/sketches, exploration of texture, material, lighting (3D &2D)
Sketchbooks are always good to show for any course!
Why are you applying to a school and probably getting out with 10s of thousands of dollars in debt? If I had a portfolio like yours I’d go straight to finding work at a studio. There’s many looking for remote work or you can can start a grand adventure and move to somewhere you get work. You’re young! I assume. This is the 21st century you don’t need a college degree, especially to do this kind of work. IMO Really a degree is only useful anymore with medicine, the applied sciences like engineering, or law school. But I also agree with part of what previous responder said. It wouldn’t hurt to broaden your repertoire. But dang! Excellent stuff!