Builds in this game are highly item dependent. A build can in most of the cases not be separated from its items. Like this one for instance.
If you have to ask in what order to put skills and attributes for this build, I’d say you are still a beginner.
On youtube Rektbyprotoss has a guide for how to level a demolitionist https://www.youtube.com/watch?v=dhBjO80zK1Q&list=PL-7HuL5PyGEKhbkCa1JmuICYzL9fpA72V&index=2 which should take you far.
If you are interested in play DW melee from scratch basically, there are tons of those guides here with more suitable masteries Beginner build guides Compendium (for AoM + FG expansions) not saying that DW melee shieldbreaker from scratch is terrible, but there are better options for beginners.