It is very important to take high quality photos of your products to sell them online. Ideally take several images from different angles or closeups to showcase the features of your products, ensure that they are in landscape orientation (tilt your phone sideways).
If you have a good camera on your smart phone, this is fine to use but if you are likely to be listing products regularly it is worth investing in some simple lights and a desktop background to get quality and consistency across all of your product photography.
This guide here gives you some tips to help you along https://blog.hubspot.com/marketing/product-photography-tips
