Booting from a USB stick on Lenovo ThinkPad T15

Assuming you've already created the UEFI mode USB stick (I have another video for creating one), this is how you boot from a USB stick on a Lenovo ThinkPad T15. Secure Boot is on by default to stop people booting from a USB stick and bypassing Windows login with the likes of Konboot (a very useful tool). But there are times you need to boot from USB so will have to disable Secure Boot to do this. I don't see Secure Boot much so keep forgetting it exists and wondered why I couldn't boot from USB. I've been in IT for years and even I miss things at times. Maybe useful for someone. Uploaded for my notes.