How to know your username in GAS app?

here's guys app go to your profile in top right and to see your username that's where you just under a full name you see a username also you can go to edit profile and then then just see this is your username at symbol and your username why you need that because yeah in a gas app actually you can search for for people by their username so imagine someone has this uh so yeah then you can just search for these people like that