i did mine from scratch , no copy-paste involved except copy a few line in stackoverflow when i got stuck and had to google it. you should too. the point the the whole fcc course is you do it by your self. not copy-paste. i don’t know what the others think but i think you should do like me tho.
For the build projects on the front end, yes I did. There were a few spots where I cut and pasted a few lines to do some specific thing - but I always made sure I understood it and usually had to change a few things.
For later projects like the backend stuff, it’s not uncommon to use a boilerplate template like express-generator. For React, it’s common to use something like create-react-app. These just create the basic framework off of which to build. I think they even recommend clementine, basically doing the same thing.
But I didn’t need them for the tiny projects on the front end. I’d avoid that - you need to learn how to put the basics together.