As the title says wanted to learn an instrument that is preferably cheap to buy and has easy learning curve. Was thinking about flute since I have one lying around but could not find any tutorials and turns out even blowing the air has a technique(tried it for a few hours). So should I try to learn flute or are there better options out there?
Depends.
No instrument (or fine art) has an easy learning curve, unless you have a really good "ear", which means you can hear something and immediately play it to tune (or sing). It takes years of practice and rigor to be able to produce a sound which is pleasant to hear. Like how you mentioned, a wind instrument is not about "blowing"; it is literally how you pass air into a chamber. Most would think a trumpet is blowing air, but it is not, you kind of like spit into the mouthpiece.
Youtube will teach you nothing. A tutor has to be there to tell you:
1. How to hold the instrument. (posture)
2. Read score. (skill)
3. Tell if your scales are on point. (warm up)
4. Tell if you are in tune. (tone)
5. Tell if you are in rhythm. (timing)
A good overall instrument to learn is -- the piano. Which can be augmented at home using a Casio keyboard. The tutelage will help you:
1. Music theory.
2. Coordination for both hands.
3. Can accompany any instrument (or be played solo).
4. Is not strictly wind (trumpet, tube, flute type) or string (violin*, viola, cello).
5. Class of it's own.
6. Less taxing physically.
Indian classical instruments would be more difficult. Since there is no score. Solely really on tonality of ear, and putting it to practice. Western you can read and implement.
*learnt 7 years at school.