There are so many different tools. More than i can list, but here's what's off the top of my head:
Engines:
- Unity
- Unreal
- Godot
- Game Maker
- Construct 2
Modelling:
- Blender
- 3DS Max (not free, but maybe educational plan if student)
- 3DS Maya (not free, but maybe educational plan if student)
Graphics
- Pain
- Gimp
- Paint.net
- Photoshop
- Krita
Audio
- Audacity
- FL Studio
Also, there are tons of people who would be willing to collab in areas you fall short int. There are also tons of sites that offer free and buying resources (sounds, art, examples).