Wonderful thinking! If Hydrogen gets $$1$$ electron, it will have $$2$$ electrons in its $$n=1$$ orbit. That makes Hydrogen stable. So, Hydrogen's valency is $$1$$. Also, Helium already has $$2$$ electrons in its outermost orbit. So, it is already stable, and doesn't need to get or give away electrons. So, its valency is $$0$$.
As we discussed earlier, atoms have an equal number of electrons and protons. This number is called the atomic number and is represented by $$Z$$
$$\text{Atomic Number}$$ $$= \text{Number of protons}$$
• $$2$$
• $$3$$
• $$4$$
• $$8$$