If the sketchUp model was made with the intent of being an OpenStudio/EnergyPlus model, that is if it has geometry grouped as you would group spaces in OpenStudio; spaces enclosed in clean volumes, then you could use the experimental user scripts as described in this post to create OpenStudio spaces from SketchUp groups. This experimental workflow acts kind of like a light weight plugin with an OSM-to-SKP translator, and an SKP-to-OSM translator to move back and forth between the formats.
More than likely the SketchUp model sent to you doesn't look very much like what you would want for an energy model. It is probably more of an architectural model, maybe thick walled, and not grouped as needed for an OpenStudio or EnergyPlus model. There are two options here. One option is to copy the floor planes and make loose top level surfaces as a diagram, and then extrude that into spaces. You will have to go back and add fenestration. The second is to use the model as a guide, and in essence trace over it. You will want to group the imported geometry, and then put it on a layer you can turn on and off. It can also be really useful to create a section cut through the imported geometry so you can show or hide as much of it as you want. If you have more interest in that I can find some old images showing the technique. It isn't magic, still requires manual work, but seeing the new and imported geometry on top of each other makes it quicker and gives confidence in the accuracy. Below are two links to videos that show how to model from plans or elevations. Similar technique is what you would use for 3d.
Modeling from Plans
Modeling from Elevations
