In addition if you've never made prints before trying to build an enlarger is going to be that much harder. You'll never know if the issue is something with the setup. Or if you've made a mistake in making the print.
If you want to make enlargements I'd look for a smaller camera and enlarger. Get the print making process down with that setup before trying to build your own enlarger for 8x10.
If it was me for the 8x10 enlarger I'd look for an old heavy monorail. Some thing with two tripod mounts. Usually cheap because of the weight. Take off the back. Fix a light source. Aristo? Or home made. Bolt the two tripod mounts to a level table. Project on a wall.
You've got all the issues. Making sure the camera and wall are perfectly aligned. Creating a negative holder system. Plus what ever else crops up during building. It's doable but it's not some thing I'd suggest until you've see how a commerical enlarger works or in some cases doesn't work.