Dock Not Showing

Please uninstall AVG, it is completely worthless (as are all Mac AV apps). Mac OS is extremely secure and if simply kept up-to-date and otherwise left alone it will remain so. Mac OS does not require nor does it benefit in any way by having any third party antivirus apps installed. Please locate AVG's uninstall instructions and use that to uninstall. Also, please do the following

Please navigate to the Mac App Store or navigate to www.Etrecheck.com and download the free version of EtreCheck. Once you have you downloaded the app and installed it, please run the report and save it. This report will help us get a good idea what has been installed on your system and help us be able to diagnose what may be wrong.

When you have your report, you can attach it when you reply to this message and we can then review it and help you determine what is needed to get your system running well again. 

For instructions on how to download your EtreCheck report and attach it to your reply to this message please click https://discussions.apple.com/docs/DOC-250000211

System Preferences - Dock then select your preferences.

By chance do you have any antivirus, cleaning or any other third party utilities installed on the computer??

To solve problem follow Click on FINDER ON HOME SCREEN (top left) then SERVICES > SERVICES PREF > Click LAUNCHPAD/DOCK > then UNTICK TURN DOCK HIDING ON/OFF (services will come up on any top left program header)