If you want a clean install, you can also download a legit Windows 10 copy from Microsoft directly. Use the tool to create a flash drive image and boot to it. Lenovos usually have a button called a Novo button that gets you into the BIOS if your system doesn't have a boot selection method easily found. One thing to note is to download either the ethernet or wireless drive from Lenovo just in case neither are installed with Windows. Once installed, I believe Lenovo has a driver tool that will either install automatically or at least tell you which drivers you need. Like others have said, Samsung for SSDs would be my preference. Get a Pro if you can afford it, an Evo if you have to. I've also had pretty good luck with the Crucial 525GB SSD. It's like $160 on Amazon. Stay away from the Western Digital ones. I've been reading a lot of negative reviews after they bought Sandisk. For a rotational drive used as a primary drive, get a 7200 RPM drive with as much cache as you can find. For storage, a 5400/4200 RPM drive is better for battery life. Seagate is fine and usually cheaper. When you get ready to replace the drive, this will probably be the manual. I've never had good luck cloning from a larger drive to a smaller one, so you might have to use a backup program. I've used this one, called Fab's, extensively: https://www.fpnet.fr/ If you have questions or run into problems, I'd be happy to help. I own a computer repair shop and do a lot of upgrades.