I taught recorder to all my middle school general music classes. Since the embouchure is pre-made, you only need to learn the correct direction and speed of the air, to get a decent time. The fingerings are reasonably simple, and within a couple of weeks, you should be able to play almost 2 full octave, and a few of the possible chromatic notes as well. Now - the recorder does NOT easily play every single sharp and flat that is used in modern (OK - last 200 years!) music - so expect to learn folks music, Renaissance, etc. dances, etc. You can get a decent soprano from Yamaha - plastic, study, yet well-made. There are also terrible cheap ones out there, that will sound like you are torturing rodents. You can get a beginners' book, and learn to read music as you go - better than just playing by ear, although that is a good skill to cultivate, also.
The flute (I am a professional flutist since 1973) has a difficult embouchure ( mouth/lips/tongue placement and usage) issue, although the fingering/key system is not complicated..
The clarinet has a red, which must be fairly often replaced, and chosen to suit your mouthpiece AND your playing abilities. It has MANY keys, because it's acoustics need them to navigate some of the inherent tone generation and intonation challenges of the instrument. Easier than the flute to start on - but I cannot choose one over the other for difficulty saw you progress. Saxophone is easier - bigger, looser embouchure, fewer keys - you could almost say, a cross in difficulty between the flute and the clarinet.Get a recorder and book - you will be playing a melody today!