Install the Instagram app and sign in to your account
Go to your profile
Tap the menu icon (three lines)
Tap Settings and privacy
Tap Audience and visibility
Turn on Private account
Confirm the change when prompted
Review who can see your content
Approve followers you want to allow if you receive follow requests
Check your Story settings (optional)
Go to Settings and privacy > Audience and visibility > Story controls
Adjust who can view your Stories (including Close Friends if available)
Remove followers you do not want to see your content (optional)
Go to your profile > Followers
Tap Remove next to the follower you want to block
Block accounts you want to prevent from interacting (optional)
Go to the account profile > menu icon
Tap Block