Goods are basically anything you buy that aren’t services. So materials, fuel, tools, vehicles, books, furniture, uniform, storage boxes, plants, etc. etc. If you can pick it up, kick it, sit on it, or throw it it’s goods!
Remember that to be able to recover VAT on goods they not only need to have been bought in the last 4 years, but you still have to own them at the date your VAT registration begins, so bricks you’ve already used in previously invoiced jobs won’t have any VAT claimable, bricks sitting in your yard you can. So you may need to do a stock take as on the day you register in order to apportion any prior bulk purchases.
The basic premise of VAT recovery is that you can only recover VAT on things you’ve bought where you’re going to be using those things to generate income that you’ll be charging VAT on.