Should the government of any country get involved in the number of children the citizens should have?
Difficult to answer; more a matter of opinion
If you mean something else the most overpopulated countries according to Pew Research are china (1.4 billion) and India (1.3 billion).
while overpopulation is a serious issue and must be addressed, taking away peoples freedom to make decisions about their own life is not ethical. However, there are steps the government can take to slow down the rate of population growth. Free and easily-accessible contraception can help prevent "surprises" ,although if you don't agree with contraceptives there are other options such as Raising awareness on the effects of overpopulation , particularly in countries where 8 or more children are not uncommon and teaching that there are other options for women than only raising a family.
Unfortunately, large families means less strain on the family as many hands make for light work. If the workload was lessened, there may possibly be a sharp decline in birth rates.
Again, this is an opinion. If you meant something else entirely, feel free to ignore this!