Referencing

If coursework for science for instance essays will include others people work/ideas in your own words, won’t the whole thing have to be referenced.
I don’t get this, what is the point.
You could just copy and paste and reference. How does it make it your work?

Undergrad uni level

If you incorporate other peoples' words or ideas, they need to be referenced.

The work that you'll be doing could include analysing, reviewing, comparing, contrasting, criticising etc what others have done. And writing up results you've got from your own experiments. That's all your own work.

In the above example, Darwin's conclusions should be referenced. But if you wanted to compare them against, for example, the text of Genesis in the Bible (which would also be referenced), the actual analysis would be your own work.