Maybe take the tour and follow the links.
As per CharlesV, MX tools, maybe Lucky Backup, Deju Dup, File Sync or others for DATA backup.
MX Cleanup, Timeshift, MX Snapshot - preferably in that order, and MX-Live-USB-Maker, can make it writeable with either persistence (many types) and/or MX-RemasterCC.
Use MX Package Installer first, MXPI, or Synaptic Package Manager.
Check MXPI before installing from outside sources, can often be done OK.
MX isn't Ubuntu, or pure Debian, don't add Ubuntu PPAs.
Don't permanently enable some repos, MXPI Testing & Backports Repo temporarily enables their repo to install the package, then disables it to avoid dependency problems.
If installing and AHS kernel, you can go "whole-hog" as D.O. put it, and enable the AHS repo permanently, but it's not really necessary, but mayb preferable if using an AHS kernel. The AHS kernels also temporarily enables the AHS repo while installing. AHS kernels, Testing, Backport repos, and I believe flatpaks packages must be updated manually, i.e. open MXPI and install the newer package. Frequently check MXPI>Popular Apps>Kernels for new AHS kernels, this is different than other distros. LTS, or "regular" kernels do autoupgrade withing MX Updater (green box).
Install:
thunar-media-plugin
++EDIT++ thunar-media-tags-plugin But it doesn't appear to be providing the additional audio tab, likely due to the 4.18 Xfce upgrade.
gtk-hash (they may have it installed by default)
appimagelauncher if you intend on installing appimages.
MXPI>Enabled Repos>user-installed-packages install before installing MX-23
This creates a file in your home folder, with most of your personally installed packages, except Flatpaks, Snaps, AppImages, etc. titled: manually_installed_pkgs
Snaps only works if you use systemd, not SysVinit (in QSI>Info), can be changed in MX-Boot Options.
QSI can save the file to home folder titled sysinfo.txt but it if changed it's incorrect, e.g. newer kernel, enabled a new repo.
Maybe install:
indicator-sound-switcher
MasterPDF fill in pdf files, not sure which one.
MX Tweak>Panel - - Backup current panel configuration.
Most of this is accurate:
https://www.youtube.com/watch?v=EO7yd5yWN7c
I like the firejail, firetools, fire profiles, and L,R,U,D & UIJK window placement, I forget others.
Again, MX Tweak, Boot Options
One biased suggestion: MX Tweak>Theme:
Matcha-dark-aliz, mx-comfort-dark-thick-border, Paprius-mxblue-dark
Choose a thick border one because, the windows are very hard to grab otherwise - small pixel selection area.
Welcome and Good luck