Where do i find screenwash motor

Located on the the screen wash tank. Easiest way to get to it is to remove the left hand front wheel arch liner.

 

They're a fairly generic part, often not even brand specific, so any parts place should be able to get you a pattern one. If you haven't got anywhere local, try partsinmotion  - if they don't list one, their support chat are really good and should be able to source one. 

Does it need a motor, or a fuse or maybe the washer fluid thawed out and a filled with stuff that does not freeze?

 i bet your fuse has gone