As stated, I5 has built in GPU, albeit not as good as the one you are waiting on. It will do the job to get everything else configured though.
You might need to go into the BIOS just before installing your discreet GPU to tell the Motherboard to default to the PCIe buss for GPU usage too, as sometimes the PC doesn't think about the new GPU and will try to use the iGPU instead... but that would even be a potential issue (and easily fixed if so) even if you had the GFX card installed before you ever first powered up your build.