Yes, that's correct! During a chemical reaction, the number of atoms is conserved. This principle is known as the Law of Conservation of Mass, which states that mass cannot be created or destroyed in a chemical reaction.
While the atoms may rearrange to form new molecules and compounds, the overall number and type of atoms present before and after the reaction remain unchanged. For example, in the reaction between hydrogen and oxygen to form water, the two hydrogen atoms and one oxygen atom combine to form two hydrogen atoms bonded with one oxygen atom, but no atoms are lost or gained in the process.