Since atoms are NOT the smallest thing in the universe, what are they the smallest of

Please help me

It's not polite to ask a question and then delete it, particularly when someone has spent time answering it, only to find it isn't there when the "submit" button is pressed.

For your information ...
Van der Waals forces encompass all intermolecular bonds (forces), which include London dispersion forces, dipole-dipole attractions, and hydrogen bonding.

London dispersion forces exist between all molecules.
Dipole-dipole forces exist between molecules which are polar.
Hydrogen bonding exists between molecules which contain H bonded to N, O or F and the hydrogen forms a weakly covalent bond to the N, O or F of an adjacent molecule.

And by the way, atoms are the smallest particles of specific elements.

Not completely sure what you're asking. Atoms make up molecules. Protons, electrons, and neutrons make up atoms.