Use the selection tools rather than trying to draw freehand. The pen tool would be a good choice because you can edit the lines after creating them, but the eliptical marquee tool would produce a realistic eye shape, and you can use Select > Transform selection to fine tune. Then there are Shapes, and if the shape you want it is not already available, Google Photoshop Shapes eye would no doubt find what you are after. Then there is the grid that you can use with Snap to grid, or custom brushes..... I bet even the best Photoshop experts use aids and shortcuts to speed up the process, and to help them create cleaner lines.
But you asked for a tutorial, and Google seems to have lots to chose from
i'm seriously losing my patience with Photoshop bc i can't even draw the outline of an eye without having it all broken and curved. i use the mouse pad thing so its harder for me to focus it. Are there any tutorials or tips that you can share with me?
You sound like you believe that an eye is the simplest thing to draw. No offence intended but you question is so broad that you might be one of these people who have never drawn an eye or anything else before using things like pencil and paper and expect that using Photoshop will magically make them capable of doing this. And you also did not say if you are trying to draw an eye from scratch without any reference or if you are trying to trace it.
Welcome to the forum.
For "anime," I think that you are using the wrong program. Adobe Illustrator will be much easier, and as it creates Vector, you can Scale with no loss in quality.
Photoshop is a digital Image manipulation program, and works with pixels, though it does have some Vector capabilities. AI is Vector to begin with, and offers much, much more.