>>1988802First off, you should avoid using strokes at all times, but if you must know it's under the fill and stroke -> stroke style submenu (inkscape, there's probably an equivalent to that in illustrator)
This is how I would do this. The red dots indicate nodes. You should not need more than this for these kinds of shapes. Also generally use elipses for eyes, even when it's a bit wobbly in the source, since eyes are always natural elipses, unless specifically deformed.