I want to use my site to have a registration signup form, for a golf outing, but I also want to have a product in there that they can select 4 different options and then charge their card once they click signup. Is that possible or how would anyone recommend I do that?
If you need to have a calendar with available dates for the options, then your best bet would be to use a “Bookings” app (https://apps.shopify.com/search?q=bookings).
If you just need to have a product with 4 options, then you can add product variants to your product, to show a dropdown with different options/prices.
https://help.shopify.com/en/manual/products/variants/add-variants
If you need customers to put in additional information (beyond their name + email + address + phone number == which are all captured by default at checkout) then you would probably want a “Custom Product Options” app (https://apps.shopify.com/search?q=custom%20product%20options) so that you can have extra fields on the product page, that they can fill out when adding the product to their cart.