Installed git 2.19.2.1 on manjaro linux - connecting with or without SSH-Keyset

dear experts,

i just installed git 2.19.2.1 on manjaro linux

Pakete (1) git-2.19.2-1

Gesamtgröße der installierten Pakete: 34,81 MiB
Größendifferenz der Aktualisierung: 0,00 MiB

:: Installation fortsetzen? [J/n] j
(1/1) Prüfe Schlüssel im Schlüsselring [#######################################] 100%
(1/1) Überprüfe Paket-Integrität [#######################################] 100%
(1/1) Lade Paket-Dateien [#######################################] 100%
(1/1) Prüfe auf Dateikonflikte [#######################################] 100%
(1/1) Überprüfe verfügbaren Festplattenspeicher [#######################################] 100%
:: Verarbeite Paketänderungen…
(1/1) Installiere git [#######################################] 100%
:: Starte post-transaction hooks…
(1/3) Reloading system manager configuration…
(2/3) Creating system user accounts…
(3/3) Arming ConditionNeedsUpdate…

connecting atom/ on linux with GIT and github, See here; heard that this would be but very simple from the command line and linux… Set your email: https://help.github.com/articles/setting-your-commit-email-address-in-git/

After uploading keys, test your ssh connection: https://help.github.com/articles/testing-your-ssh-connection/

Switch repo to use ssh rather than https: https://help.github.com/articles/changing-a-remote-s-url/#switching-remote-urls-from-https-to-ssh

but if i look at my atom editor i have the options of

connect with GIT
connect with GITHub

well whats the difference here between git and github!? why cannot add some commits while i see the git with create detached commend - nothing happens here.