Plugins are not appearing

Hi

I’m New to Word Press…but i’m facing a strange problem

i installed it here, tried different themes, my problem is :

When i download and install plugins, and activate them, they do not appear in the customize…

here’s my problem in Screen shoots:

These are my current installed plugins:
https://s11.postimg.org/5pyoqyzur/Installed_Plugins.jpg

and this is what i see in appearance/widgets
https://s28.postimg.org/vry8fqhb1/available_plugins.png

even in appearance/customize they are not showing…

Tried difference themes, still not appearing.

any thought?

Thanks in advance.