Hi,
1. Yes. Go in the menu System>Shipping methods and click on the "new" button. All the shipping plugins besides the "Manual" shipping plugin will automatically calculate the shipping fees. As you'll see, you have one plugin per carrier. So which one to use depends on which carrier you're using for shipping. If it's UPS, then you need to use the UPS plugin, etc.
2. If you update the Joomla 3 website to Joomla 4, then there is nothing to do. You'll keep everything in HikaShop.
If you want to start from scratch on a new Joomla 4 website and you want to migrate the HikaShop data to the new website, you can do like this:
www.hikashop.com/support/forum/install-u...joomla-4.html#342407