I can't hear any sound. I've just installed the latest LTS Ubuntu version

I'm a new Ubuntu user. I need to debug my sound problems. Already tried some of the codes suggested by other users, but don't get the way to solve it. I'll be grateful if anyone can help me

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: pulseaudio 1:13.99.1-1ubuntu3.12 [modified: usr/share/pulseaudio/alsa-mixer/paths/analog-output-speaker.conf]
ProcVersionSignature: Ubuntu 5.11.0-40.44~20.04.2-generic 5.11.22
Uname: Linux 5.11.0-40-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/hwC0D2', '/dev/snd/pcmC0D3p', '/dev/snd/pcmC0D2p', '/dev/snd/pcmC0D1p', '/dev/snd/pcmC0D7c', '/dev/snd/pcmC0D6c', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Thu Nov 11 14:17:43 2021
InstallationDate: Installed on 2021-11-09 (2 days ago)
InstallationMedia: Ubuntu 20.04.3 LTS "Focal Fossa" - Release amd64 (20210819)
SourcePackage: pulseaudio
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 06/07/2021
dmi.bios.release: 1.34
dmi.bios.vendor: HUAWEI
dmi.bios.version: 1.34
dmi.board.asset.tag: NULL
dmi.board.name: NBLB-WAX9N-PCB-B2
dmi.board.vendor: HUAWEI
dmi.board.version: M1010
dmi.chassis.asset.tag: NULL
dmi.chassis.type: 10
dmi.chassis.vendor: HUAWEI
dmi.chassis.version: M1010
dmi.ec.firmware.release: 1.34
dmi.modalias: dmi:bvnHUAWEI:bvr1.34:bd06/07/2021:br1.34:efr1.34:svnHUAWEI:pnNBLB-WAX9N:pvrM1010:skuC331:rvnHUAWEI:rnNBLB-WAX9N-PCB-B2:rvrM1010:cvnHUAWEI:ct10:cvrM1010:
dmi.product.family: MateBook D
dmi.product.name: NBLB-WAX9N
dmi.product.sku: C331
dmi.product.version: M1010
dmi.sys.vendor: HUAWEI