I just need to accept credit cards and don't want or need a ecommerce website

I just need to accept credit cards and don’t want or need a ecommerce website.

No problem. What you can do is create a Checkout only store. It’s available when you create a new store if you scroll down under the advanced section:

You’ll still be able to share checkout links for products and invoices but there will not be an ecommerce website to setup or maintain.

You can create direct links to purchase products by opening up the product details screen in your dashboard and clicking on the Variants tab, then the Browse sub-tab and scroll down to the table. On the right you’ll find the Checkout URL action. Click on that and it’ll copy the direct link to purchase that item that you can send to your customer.

If you want to include multiple products you’ll either need to edit the URL to include the additional items (if you’re comfortable with that) or instead use an invoice.