Would an SSD speed up a slow Laptop

[ppppenguin]

First question: have you made a bootable memory stick? Just copying the files to it doesn't work. In Windows Rufus is free and works well though I see it only works for Windows 8 and above: https://rufus.ie/en/ If you're making the USB stick on a PC with W8 or later then you'll be fine. Otherwise there's a legacy version of Balena Etcher that ought to work in W7: https://etcher.balena.io/

If you've made a bootable memory stick and it still isn't working then you will need to go into the BIOS and change the boot order. You need to press the correct key to do this. Varies from computer to computer. I've seen Esc, Del, F8 and F12. It usually flashes up on the screen for a second during boot. I often find that you need to press the key many times during boot to make sure you've actually pressed it at the right time.

Then you should be able to look around the BIOS settings and make USB first on the list of boot drives.

Some (most?) PCs also have a key to allow you to choose boot device, if it's pressed during boot. Again it may flash on screen during boot. This can be easier than altering BIOS settings.