This person's instagram says she has over 300 posts but nothing is displayed publicly.... ?

I am not familiar with how instagram works, so if i follow her on instagram, am i automatically able to view her 300+ posts (pictures and videos), or does she need to approve my 'following request' in order for me to view her stuff? I have noticed that most accounts on instagram are public, but that sometimes some accounts won't show anything publicly. Does that mean one would need to make an account and follow them in order to view their posts/pictures? Or do they need to confirm your follower's request in order for you to view their stuff? Thanks in advance.