No Ability to add new plugins or themes

I recently hosted with Dreamhost using one clock install for wordpress. The first site I did this with was succesfull. I was able to add plugins and install new themes.

This latest site I am trying to get up and running has been a completely different experience. I followed the exact same procedures, but there is absoultely no option to add a new plugin. In themes, the tab to “install theme” is completely missing.

Please help.