These fingerings can be found in various fingering dictionaries. A common one . A group commonly found around D 2 and F 2 . You can do smaller intervals . You can also get wide intervals .
Major thirds are possible also.
You get the idea. You can also create multiphonics with beat frequencies in them, because they are close to, but not quite in tune. As you can hear, sometimes the beat speeds are controllable. The intentional bending of a pitch upward or downward, using the embouchure, not the keys. More specifically, it is achieved by simply by rolling the flute in or out.