

It’s an action vs a state of being.
I made sure he died is making sure that the action of dying was completed. In that sense it sounds like you contributed to them dying. E.g. a mobster telling his boss he made sure someone died.
I made sure he was dead, is confirming their state of being as dead. E.g. a professional would ensure someone was dead before they’re cremated.
There is a lot of nuance in there though. E.g. a mobster might also make sure someone was dead after e.g. shooting them. (But again it’s checking their state of being rather than ensuring their act of dying was complete. I.e. finishing them off)

Ive had an ender 3 pro for about 5 years. Setting it up was straight forward I just followed a YouTube video which had some tips to help make sure the frame was square.
Ive never used the included slicer. Only Cura which is pretty great.
It’s definitely not the fastest but it’s a great beginner 3d printer and there is no requirement to tinker with it. I just level the bed and print each time. No problems 5 years in. (I did have to replace the removable print bed top at one point but that was partly because I’d gouged it before I learned how to level it)