Change "Add to cart" text

Is there any way you could link us a Webpage with the problem?

Of course!
https://www.lacharla.se/?post_type=product
Though it looks OK from a computer but the “Add to cart” collide when looking from a mobile.

Look at reducing the font size on mobile, e.g.:

@media only screen and (min-width : 321px) {
    .woocommerce .product_type_simple {
        font-size: 10px;
    }
}

Oh i meant changing the text, not the size:) I want to change it to K?p (Buy) instead of Add to cart. Is this possible?

If this is a WooCommerce question you need to post here: https://www.ads-software.com/support/plugin/woocommerce#postform