Can I travel to the Netherlands via Turkey with UK refugee travel documents?
For visa requirements of the Netherlands, see https://www.netherlandsworldwide.nl/visa-the-netherlands/refugees-stateless
Did a country outside the Schengen Area issue your travel document for refugees or stateless persons? Whether you need a visa depends on your travel document.
The page goes on to explain that you do not need a visa with a document issued by the UK if the document says "Convention of 28 July 1951" or "Convention of 28 September 1954." It also underscores that other Schengen countries may require you to have a visa, so you will need to check the requirements separately for every country you intend to visit.
If your UK document is something else you will probably need a visa to visit the Netherlands.
For Turkey, you can transit without visa only in certain airports (including the major international airports) and only if your scheduled departure is within 24 hours of your scheduled arrival.