Canva is one of the best resources that will help to enhance your website design. It has many options that can go from adding a simple element to a banner creation. You can even design animated posts.
There is a free version of Canva that is helpful to give you a start. However, the paid version has many more options that will help your designs go to the next level.
From removing backgrounds in pictures to resizing the image of your banner or a simple post, the best part about Canva is that it also has a design school that will give you the tools to learn more about their site through some of their helpful tutorials.
Give the design school a try and learn with the tutorial. It will allow you to explore your creativity side.