Wanting to know how hard would it be to do a decking myself and what would be the easiest way of doing.
Welcome to Workshop @bomba. You've certainly come to the right place for advice and support. We have lots of friendly and experienced members who would be happy to help.
Your post immediately reminded me of our most popular decking project on the site - D.I.Y. deck from scratch by @Tara86. Tara and her partner built it from scratch and it was their first deck project, so she should have some great feedback for you.
You might also get some inspiration and information from our Top 10 most popular deck projects.
And this is also a great place to start - https://www.bunnings.com.au/diy-advice/outdoor/decking/how-to-build-a-deck
Looking forward to seeing your project come to fruition, and seeing the community assist along the way.
@bomba FYI it's decking month @ Bunnings. Call your local store and see if they are doing any DIY's on it atm. Last weekend we did a major decking event and had customers building decks with us in-store.