MX Linux Forum

1) Am I missing some apps which I need to install alongwith the basic Gnome?
2) I was want the System sounds working the same way as it works with XFCE. I couldn't find an option to do that.
3) I will be using Gnome Shell so if I want to remove the other already installed Desktop Environments ...

I'll leave others to reply to the rest, but note that the System Sounds tool is an MX app, specially created by MX Devs to work with XFCE, the default DE for MX. You will have to check if a similar app (or maybe extension) exists that works with Gnome.

Gnome is also much more systemd-focused, so ...

Although I love using XFCE, but due to Gnome's integration with Google Drive and Google Calendar (through Online accounts and Evolution), I am using Gnome Shell. So, I have installed Gnome Shell on my system.

After using it for a while, it seems I am missing a few tools, may be because when I ...

I use Evolution because of Google Calendar integration.