AMS1117-3.3 from 5VDC show 0.09vdc
You have the 3.3V version not the adjustable version as shown by the part number.

See the datasheet under electrical characteristics: the regulator wants a minimum load of 10mA.  If you directly measure the unloaded output, your multimeter's impedance is too high for the chip to regulate.

Page four of your linked datasheet also states that the output capacitor is not optional.