I want to use an arduino board to upload images that will be outputted by the board to a projector, and it also has to control a stepper motor at the same time.

Ps. I am new to ardiuno but I know this is the best way to go about doing this, also it would be great if I didn't need to have a computer plugged-in but not necessary.

Itty bitty images?

well its black and white images but they will be kinda big depends on the projectors resolution

This really isn't a project for an Arduino, unless your intention is to display extremely low resolution monochrome images.

Try a Raspberry Pi, if you want a small box to connect to a projector. A BeagleBone, with appropriate video output shield, is another option.

oh yeah I've heard of this but didn't know what to use it for but thanks.