My MacBook doesn't show pendrive and also not working internal speaker

In the Finder, select the Preferences… item in the Finder menu. See what's checked off in the General tab (which affects the Desktop) and Sidebar (which affects what shows up in the left side of Finder windows), and adjust the settings to taste.

If it's not just a matter of the preferences being set (by default) to hide the icon, report back.

As far as the internal speaker not working, that's logically a separate issue.