Hello twiggy and welcome to the Community.
There are many resources for designing decks.
Below is an article about:
How to Choose Your Decking MaterialYou will find if you click on the different manufactures, you will open links to their web site, where they have many design ideas.
This LINK will take you to the Home Depot site for decking. This could be great place to see many material options available to you. When looking at a particular product, scroll down to product overview and check out the installation information. For example here is the LINK to Trex web site
One of the best places to get started would be to visit a Pro Associate at your local Home Depot. Be prepared with information about the Size and height of your planned deck. They can use the deck design software to help create a design and give you a price approximation. They can also discuss material options.
If you would like to share more details of your situation, like your space, budget, what you currently have, are you starting fresh, I would be happy to be more specific.
Thank you for your inquiry.
Charlotte