Im a web developer and im new in Ubuntu, I have days trying to install apache2 to work with php.
But I always get this error starting Apache2:

Job for apache2.service failed because the control process exited with error code.
See "systemctl status apache2.service" and "journalctl -xe" for details.
invoke-rc.d: initscript apache2, action "start" failed.
● apache2.service - The Apache HTTP Server
   Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled)
  Drop-In: /lib/systemd/system/apache2.service.d
           └─apache2-systemd.conf
   Active: failed (Result: exit-code) since Mon 2019-08-26 01:23:22 CDT; 29ms ago
  Process: 8725 ExecStart=/usr/sbin/apachectl start (code=exited, status=1/FAILURE)

ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: (98)Address already in use: AH00072: make_sock: could not bind to address [::]:80
ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: (98)Address already in use: AH00072: make_sock: could not bind to address 0.0.0.0:80
ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: no listening sockets available, shutting down
ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: AH00015: Unable to open logs
ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: Action 'start' failed.
ago 26 01:23:22 alejandro-TP201SA apachectl[8725]: The Apache error log may have more information.
ago 26 01:23:22 alejandro-TP201SA systemd[1]: apache2.service: Control process exited, code=exited status=1
ago 26 01:23:22 alejandro-TP201SA systemd[1]: apache2.service: Failed with result 'exit-code'.
ago 26 01:23:22 alejandro-TP201SA systemd[1]: Failed to start The Apache HTTP Server.
Procesando disparadores para ureadahead (0.100.0-21) ...
Procesando disparadores para systemd (237-3ubuntu10.25) ...
Procesando disparadores para man-db (2.8.3-2ubuntu0.1) ...
Procesando disparadores para ufw (0.36-0ubuntu0.18.04.1) ...
sh: 0: getcwd() failed: No such file or directory

I’ve tried to reinstall apache, but it hasn’t work for me…
Does anyone know what can i do? It would be very helpful.
Thanks