Instagram does not let you fully hide your followers list from everyone
Set your account to private to limit who can see your followers
Go to your profile
Tap the menu icon
Tap Settings and privacy
Tap Account privacy
Turn on Private account
Remove followers you do not want to see your list
Block specific users to prevent them from viewing your profile and followers
Restrict users if you want to limit their access without blocking
Hide your following and followers indirectly by using a separate private account
Keep your profile information minimal to reduce visibility