Can I install prezi plugins on the web-based wordpress?

I am a history professor, and one of my wordpress blogs is a resource where my students and I can post things that aren’t necessarily supported by university applications like blackboard. I am attempting to build a page where I can post group presentations my class made this semester. Some of these presentations are Prezis. I found a plugin that will allow me to embed a prezi, but I don’t seem to have access to the plugin admin. I use the web-based themes for wordpress. Do I have to download and install WordPress to do manage plugins? If so, is there a work around? I am not a programer and do not foresee needing to have that much access to my blog sites.

Any advice on how to embed my students’ prezi presentations is greatly appreciated. Thank you for your time,
Holly N.