is it for coloured hair only?

No definatly not. My husband and have used it for year after recommendation from hairdresser. Brillient product, lasts ages as you only use a small amount then re wet your hair after massaging in for extra bubbles

do goldwell products contain any parabens, sulphates or silicone?

I am sorry, i have no idea if they contain parabens, sulphates or silicone, i do not look for these when deciding to purchase something, i buy the product because it works for me

this product says it’s conditioner on the bottle but shampoo in the description? What one is it?

I've never bought the conditioner. Only familiar with the shampoo. I used to love Goldwell in the past,best shampoo I've ever used,no need for conditioning after wash. The Goldwell that's being sold these days,is not what it once was. Different smell,different feel, just a totally different product. Not any different than some really cheap brands. Years ago (25+years) I went to my nearest hair salon to buy it, now I wouldn't buy any Coldwell products (shampoo nor conditioner) just a waste of money.