How can u improve penis length and width?

Bigger penis. If you are very obese, weight loss can give you length back but nothing can make what you already have bigger.
Too long short wide? Any size is fine. Other than babies with penis birth defects, pubertal boys with hormonal deficiencies, or rare cases of under-development, treatment to change one's penis length or width is not necessary. For adult males, a penis with a firm erection is large enough if the penis touches the sides of the other person's opening, which is a vagina in the vast majority of cases.