Debian 11 full up; How to reduce the size?

Hello,
I have to reduce my Debian 11 since it fill the HDD.

https://wiki.debian.org/ReduceDebian

My plan is to delete what I dont need..

a) delete qemu and ispell/or/aspell and mozc and evolution and gimp
(since the disk analyzer say its big and I dont see a use in the next future)
what is ispell and aspell for?

b) When I see the logs, they are huge. Is there any possibility to reduce this?

ls -l /var/log/
Code:total 4968440
-rw-r--r-- 1 root root 1266 Aug 26 12:00 alternatives.log
drwxr-xr-x 2 root root 4096 Aug 26 12:02 apt
-rw-r----- 1 root adm 147568 Aug 26 12:02 auth.log
-rw-rw---- 1 root utmp 0 Aug 2 08:25 btmp
-rw-rw---- 1 root utmp 768 Jul 9 15:37 btmp.1
drwxr-xr-x 2 root root 4096 Aug 26 00:00 cups
-rw-r----- 1 root adm 321257911 Aug 26 12:01 daemon.log
-rw-r----- 1 root adm 185634 Aug 26 12:01 debug
-rw-r----- 1 root adm 666930 Aug 25 17:04 debug.1
-rw-r--r-- 1 root root 201961 Aug 26 12:02 dpkg.log
drwxr-s--- 2 Debian-exim adm 4096 Aug 26 11:16 exim4
-rw-r--r-- 1 root root 2049792 May 8 2023 faillog
-rw-r--r-- 1 root root 14509 Aug 16 09:45 fontconfig.log
drwx--x--x 2 root Debian-gdm 4096 Aug 22 2021 gdm3
drwxr-xr-x 3 root root 4096 Jul 22 2020 installer
drwxr-sr-x+ 3 root systemd-journal 4096 Aug 22 2021 journal
-rw-r----- 1 root adm 973385 Aug 26 11:45 kern.log
-rw-rw-r-- 1 root utmp 18704352 May 8 2023 lastlog
drwxr-xr-x 5 root root 4096 Jan 21 2022 libvirt
-rw-r----- 1 root adm 1479020187 Aug 26 12:00 messages
-rw-r----- 1 root adm 1063073 Aug 25 17:04 messages.1
drwx------ 2 root root 4096 Jul 22 2020 private
drwxr-xr-x 4 root root 4096 Feb 11 2023 runit
drwxr-x--- 3 root adm 4096 Aug 25 17:05 samba
drwx------ 2 speech-dispatcher root 4096 May 2 2020 speech-dispatcher
-rw-r----- 1 root adm 1800410968 Aug 26 12:02 syslog
-rw-r----- 1 root adm 3173044 Aug 25 17:05 syslog.1
drwxr-xr-x 2 root root 4096 Nov 14 2021 teamviewer15
drwxr-s--- 2 debian-tor adm 4096 Jan 3 2023 tor
drwxr-x--- 2 root adm 4096 Aug 16 09:29 unattended-upgrades
-rw-r----- 1 root adm 1478126384Aug 26 12:00 user.log
-rw-rw-r-- 1 root utmp 790272 Aug 26 11:44 wtmp
-rw-rw-r-- 1 root utmp 1049088 Nov 2 2022 wtmp.1
c) It looks like my system is retrieving the SRC. How to shutdown this?
ls -l /usr/src/
total 16
drwxr-xr-x 4 root root 4096 Jul 16 09:34 linux-headers-5.10.0-31-amd64
drwxr-xr-x 4 root root 4096 Jul 16 09:34 linux-headers-5.10.0-31-common
drwxr-xr-x 4 root root 4096 Aug 16 09:44 linux-headers-5.10.0-32-amd64
drwxr-xr-x 4 root root 4096 Aug 16 09:43 linux-headers-5.10.0-32-common