Typically i just design the website, but if you need help with the product design, i can try to help with that too or show you how to use Printify, but that's an added cost.
Yes, you need to pay Printify when a customer places an order. You only pay when you make sale though.
Printify will not produce your order until payment is made.
If there is no money in your Printify Balance and your linked card is declined or unavailable when a customer places an order, the order will be placed on hold. Printify requires payment for the production and shipping costs before sending the order to the print provider. If you don't have the money, you can pay it when the customers payment comes into your account.
You have three choices (maybe more):
1. You can purchase designs from designers online and add to your products.
2. You can hire a designer to design them for you.
3. You can learn to design them yourself in either Canva or another design program.
You can handle your own customer service if you'd like or you can have Printify act as your customer service. They have a service that's free with a premium subscription called Printify Connect. The customers don't know that they are speaking to an agent at Printify, because it's your customer service agent.