pull up pavers on entrance and replace with a low deck to level size 6.5 x 5 m and how to calculate how muck decking i will require
Welcome to the Bunnings Workshop community @garyangove. It's wonderful that you've joined us and many thanks for your question.
You can use this decking calculator from SpecRite to work out the amount of decking you will need. If you were to use 90mm decking boards and lay them along the 6500mm length, you'd need 377 lineal meters or 67 x 5700mm boards.
Please let us know if you have other questions.
To clarify @MitchellMc's explanation, he based his calculation on the length and width of the area you provided. He based his panel width on the popular SpecRite Merbau size of 90mm. The common size of this panel is 5.7 meters long. Taking into account the type of frame built and fixings used, plus the type of edge finish design will affect the overall amount you will need.
The general formula for decking is based on the overall decking area divided by the area covered by a single panel. It then gives you the lineal meters you will need to cover your deck. Using the decking calculator that @MitchellMc mentioned takes a lot of the guesswork out.
In order to get a more accurate count, I suggest planning your frame. Once you have your frame size you can then base your calculations on the actual area that the deck will cover.
Let me call on our experienced member @Itai for some advice as he has recently completed a part of his deck.
If you need more information please let us know.