p1 <- ne_download(scale = 10, type = "parks_and_protected_lands_line", category = "cultural")
p1 <- ne_download(scale = 10, type = "parks_and_protected_lands_line", category = "cultural")
p1 <- ne_download(scale = 10, type = "parks_and_protected_lands_point", category = "cultural")
p1 <- ne_download(scale = 10, type = "parks_and_protected_lands_scale_rank", category = "cultural")

trying URL 'https://naturalearth.s3.amazonaws.com/10m_cultural/ne_10m_parks_and_protected_lands_line.zip'
download failed
Warning messages:
1: In utils::download.file(file.path(address), zip_file <- tempfile()) :
  cannot open URL 'https://naturalearth.s3.amazonaws.com/10m_cultural/ne_10m_parks_and_protected_lands_line.zip': HTTP status was '404 Not Found'
2: In check_data_exist(scale = scale, category = category, type = type) :
  parks_and_protected_lands_line seems not to be in the list for category=cultural maybe try the other category of c('cultural', 'physical')