[SOLVED] How to generate a summary of a linear model using two conditions in R?

Assume that a dataset has the variables Age, Gender and Height. How to create a linear model based on age that only considers ages between 18 to 21.

This is what i have so far and it works, but I don't know how the && operator works in R.

model1 <- lm(formula = Age > 18 ~ Gender + Height, data = myDataSet)

But when I try adding my second condition the following error occurs:

model2 <- lm(formula = Age > 18 && <21 ~ Gender + Height, data = myDataSet)

ERROR:

 Error: unexpected '<' in:
"model2 <- lm(
  data=myDataSet, formula= Age > 18 && <"

user11916948 ANSWER:

model3 <- lm(formula = Age>18 & Age<21 ~ Gender + Height, data = myDataSet)
summary(model3)