Help needed - compression level for btrfs file system on my ubuntu 23.10

five questions i need help with

q1.
how do i check to see what compression level my btrfs file system on my ubuntu 23.10 system is using ?

q2.
how do i add an change its level an apply it to the whole system (id like to set level 4) ?

q3.
what the correct way to add/edit it into the fstab file ?

q4.
how do i check why compression level my zstd setting is at an how do i set it higher if i want ?

q5.
with zstd compression algorithem can i set it to level 5 an have work when i select it in a gui app like xarchiver
an if so how would i do that ?

when i type in the terminal
man compsize i get this

compsize(8) btrfs compsize(8)

NAME
compsize - calculate compression ratio of a set of files on
btrfs

SYNOPSIS
compsize file‐or‐dir [ file‐or‐dir … ]

DESCRIPTION
compsize takes a list of files on a btrfs filesystem (recurs‐
ing directories) and measures used compression types and the
effective compression ratio. Besides compression, compsize
shows the effect of reflinks (cp ‐‐reflink, snapshots, dedu‐
plication), and certain types of btrfs waste.

The program gives a report similar to:
Processed 90319 files.
Type Perc Disk Usage Uncompressed Referenced
TOTAL 79% 1.4G 1.8G 1.9G
none 100% 1.0G 1.0G 1.0G
lzo 53% 446M 833M 843M


im not sure if im reading it right if the lzo line means ther compression enabled
but wither it is or not id like to set for the main an 2nd nvme ssds in

my rig the compression to be zstd at level 4 an some step by step help on how to do that
this is what my fstab file looks like

an how an were do i add the compress=zstd line ?