What is the Netflix resolution on the iPad Pro 2018?
Depending on which movie you are watching or in which resolution it was taken. Mostly in FullHD, so 1920 x 1080 pixels.
The iPad Pro itself has a resolution of 2388 x 1668 pixels at 264 ppi in the 11 "version and the 12,9" version has a resolution of 2732 x 2048 pixels at 264 ppi.
Both versions have a resolution of more than FullHD which is more than sufficient.
So: You will probably be able to see every movie under 4k in full resolution.
Important here is, of course, that your Internet participates but which is usually no problem.
Enjoy the series and watch movies on Netflix.
Unlike YouTube, is there 1440p?
Here it depends again on the producer of the film. If the movie was filmed in 1440p and uploaded to Netflix, the iPad Pro can play without problems.