Open Facebook and go to your profile
Tap or click Friends
Select the three-dot menu or Edit Privacy
Change Who can see your friends list to Only me
Save the changes
On mobile, go to Settings and privacy
Open Settings
Go to Audience and visibility
Tap How people find and contact you
Adjust friend-list visibility if available
Check your profile privacy settings
Limit past post and profile visibility if needed
Review tagged content and timeline settings
Use the Privacy Checkup tool in Facebook settings
Repeat the same steps on desktop and mobile if needed