I am new a this online business too but let me tell you that 1st of all let me congratulate you is having the gutts in starting your business.
Entrepreneurs like you not only have to be careful with scamers and people who are waiting in line to rip you off you have to deal with suppliers, customers and other things.
It is not easy but at lease you give it your best shot. And you will know for sure if it works or not for you.
And there is no better way of learning a business than doing it.
Imagine if you somehow make your online business works! you will have a huge like-vending machine. Working and selling for you night and day. Earning extra income while you are working in your real job. or at home with your kids.
You mentioned that you already sold something on Ebay.
Did you already know how to sell and ship international?.
How you solve customer problems? give them a refund? track a shipment?
Those are some of the things you have to know and you can practice with used or low prices items that you have at home and don't mind to lose if needed to be. Imagine if you are testing with $200 or more dollars items. You will be out of business in no time.
Hope those tips help you in your new business