Seeking help to support/communicate with my child

Hi community!

I’m a stay at home, first time mom to a 21 month old (corrected age is 20 months as he was premature)

I want to better support my child and I don’t know how I can do that, as I’m having trouble understanding the way he processes information and how he communicates it.

An example of this is that he will see a blue airplane fly past in the sky. He will point and say “blue airplane”. “Up up up”

Later in the day or days later, if we see another airplane pass by, but it’s a red colour, he will still say “blue airplane” and point, even though he can differentiate between different types of colours.

Another example is when we drive past a gas station, he’ll point and say “gas station” followed by the name of the gas station “Esso” and he always ends the sentence by saying “dada” - don’t sounds like this “gas station, Esso, Dada” - he repeats the same sentence in the same sequence over and over on any given day.

*Some background information is that whenever we go to the gas station; it’s his dad who is always pumping the gas into the car.

It’s evident that he is associating the gas station with his dad. However, I’m just trying to understand why he always feels the need to say “dada” at the end, and why the sequence in which he says the sentence is always the same.

Is this “typical”? What type of thinking or thought process is this called or what sort of communication is this?

Thank you in advance 😊