iTunes issue

I have a MacBook with a very large iTunes media collection, so I wanted to move the music to My Cloud Home and free up space on my hard drive. I followed all of the instructions: consolidated the library, copied the iTunes folder to the MCH (I didn’t want to move it until I was sure it worked), and copied the media folder to the MCH. All of that worked fine. I then opened iTunes while holding down the Option key, and it asked me to Choose Library. I tried to choose the most recent iTunes.itl file that had transferred, but it was grayed out and I couldn’t click on it. I tried a couple of times, unsuccessfully, and then clicked on Create Library. I created a new .itl file called iTunes1and that worked. I then opened iTunes using that library and began to import the media files that I had copied onto MCH - here’s where my problem begins (sorry for the long lead-in). As the importing was happening, and even after, the hard drive space on my MacBook was going down. I wondered if it was somehow writing these files on the MacBook hard drive, so I clicked “get info” on some of the songs. In Finder it showed them, and my other MCH files, in Library>containers>com.wdc.WDDesktop.WDDesktopFinderSync>Data>Volumes>[some combination of letters and numbers]>mycloudhome>. In addition, the files being imported into iTunes are showing up on MCH in the iTunes1 folder, which is fine since I have plenty of space on the MCH. My question is - am I somehow importing these files onto my MacBook hard drive? If so, that kind of defeats the purpose and I’m clearly doing something wrong. Thanks for your help!