By the end of the century only Africa will have a fertility rate higher than 2. All the other continents have a lower rate than 2, meaning a decline in population.
Fertility rate is just one piece of the equation.
Infant mortality rate is off the charts in Africa compared to the majority of the world.
Average life expectancy is also much lower in most African nations compared to the places with low total fertility rate.
There’s a lot more nuance than even just these two other pieces. Generalizing at a continent level is really poor. A typical metropolitan couple/family is going to have less kids than a rural family in the US where cost of living is lower and pressures from religion and family are higher.
When your neighbors, friends and family are holding off from kids to pursue higher socioeconomic standards there’s pressure to live up to them or surpass them. When your neighbors, family and friends are having kids left and right you feel pressured to join them too. Just food for thought.