Hi Siri,

If you want to hide only category add this Custom CSS:

.woocommerce .summary .product_meta>span.posted_in {
    display: none;
}

For tags add this one:

.woocommerce .summary .product_meta>span.tagged_as {
    display: none
}

And for both:

.woocommerce .summary .product_meta>span.posted_in,
.woocommerce .summary .product_meta>span.tagged_as {
    display: none
}

I hope this will do the work for you.