What are the most atoms in the universe? least of all?

Most of the atoms of hydrogen and helium, the least of all atoms of heavy elements. Immediately after the Big Bang, hydrogen and some helium were mainly produced. Atoms of heavy elements are formed in small quantities in the interiors of stars and during explosions of new stars and supernovae.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.