如果你想表达你有很多衣服,你可以说:

I have a lot of clothes.

如果你想说明你有很多不同种类的衣服,你可以说:

I have a wide variety of clothes.

如果你想说明你有很多同一种类的衣服,你可以说:

I have a lot of (specific type of clothing, such as "t-shirts" or "dresses").

例如:

I have a lot of t-shirts.
I have a lot of dresses.