Effective image is half of the success and an integral part of editing. It contributes to attracting potential clients - it grabs their attention and informs about your services/products.
Still, it is up to you whether to use stock pictures or your own.
The article Adding images will help you with their uploading while Editing images will present you with the appropriate tools for changing the size, color, add a filter, etc.
Tip: watch the article Editor: getting started and learn how to customize your template and launch the website of your dream on Moto4 in a few clicks!