error in drop_na()

penguins %>% group_by(island) %>% drop_na() %>% summarize(mean_bill_lenght_mm = mean(lenght_bill_mm))
Error in drop_na(.) : could not find function "drop_na"

how can i solve error for drop_na or which package i missed to install it ?

The function is from tidyr. If you load the tidyverse package it would be included.