Migrating to SSD

I am working with a professor this summer and they gave me a 480GB SSD to install Linux on. So I made a 128GB partition on it and installed Linux Mint (Is it possible to make this partition smaller while keeping the Linux installation and everything I configured?). However, they also gave me permission to use the SSD for whatever else I like. I have a 100GB Windows image on an external 2TB HDD but my issue is being able to "install" this image to the remaining space on the SSD. Does anyone have any advice on how I would go about this and/or have any idea of what tools I would need? Thanks!
 
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