Facebook gives you a feature in which you can find out your recently added friends. This feature helps you in managing your friend list. Fortunately, you can check your recently added friends on a mobile device or on your PC. Here is the best way to see recently added friends on Facebook on your mobile device.
1. Firstly open your Facebook app
2. Then click on the “menu” (three horizontal lines) at the top right corner of the screen
3. Now, click on your name
4. Scroll down and click on “See All Friends”
5. After that tap on recent to view newly added friends.
Read here: https://getassist.net/see-recently-added-friends-on-facebook/