In Ubuntu 18.04 , the Show Application icon is at the bottom of the Dock.If you have Windows experience you may feel better if it locates on the top but not bottom to make Ubuntu much like Windows
To move the Show Application icon to top , the simplest way is to use gsettings command . Maybe you hate command line ,but that what Ubuntu is , you need to install another tool or application without using command line.
Right-click your Ubuntu desktop then click Open Terminal (Or by pressing Ctl+Alt+t) , then input below command and press Enter , it’s done ,so simple.
gsettings set org.gnome.shell.extensions.dash-to-dock show-apps-at-top true
If you want to revert it back ,just issue below command
gsettings set org.gnome.shell.extensions.dash-to-dock show-apps-at-top false
1.(Optional) If it’s the only user account whose name you want to change , you need to enable root account in case something wrong and cause both new and old account can not login. To enable root account ,just open an terminal by pressing Ctl+Alt+t,then issue below to commands to set a password for root
2.Logout the user account whose name you need to change
3.Press Ctl+Alt+F3(or F4 F5 F6) to switch to virtual console and login with root (Of course if you have another user account with admin access ,you can login gui with that account )