All the pending friend requests sent to your Roblox account are found in the Friends tab. You have the option to accept or decline the request from other users on your profile.

How to accept friend request in Roblox: Step-by-step guide Image via catbeweird (YouTube) Players can either send a friend request or accept one.

It's a little bit more straightforward to add a player on the ROBLOX Player. At the top of the home screen, you'll see "Friends" and then a circle, that has an icon of two players, saying Add Friends.