When it comes to selling on eBay tangible products I would suggest starting off with what is in your closet, under the bed, in the garage, etc.
You know that “thing” you no longer use but it’s too nice for a yard sale. You can be surprised what some of these things bring on eBay.
If you already own it, it’s almost all profit when you sell since you would like to have it go anyway. You will know everything about it or at least something about it. This is important if a prospective buyer asks questions.
Remember, we want to keep this simple so you can learn and stay with it.
Now if you found a source for a product then great, if not, don’t worry that will come in time. Let’s get good at selling and product sourcing will just fall into place, you’ll see.