I tried to make a smooth surface by subdivision function, however it modified the object like this… How can I use it to generate a object without any sharp edges?
your topology must be bad, please show the wireframe
maybe you have overlapping vertices? try an Alt M > Merge By Distance
if it doesn’t work please share your file: https://pasteall.org/blend/
uploaded…
you need to share the link 
you have flipped normals (as seen below), so go in Edit mode, select all, press Alt N (or Mesh > Normals) > Recalculate
that’s work! Thank you very much!