2008 MacBook as second monitor?
I've got a late 2008 macbook (v10.11.6, 2 GHz Intel 2 Duo, 13" I could possibly update to mojave?) and a late 2015 iMac (v10.14.1, 1.5 Ghz Intel i5, 21.5"). Is it possible to use the macbook as a second monitor, and if so what cable(s) and converter(s) do I need to buy? I've found conflicting answers on the macbook in my research.
Thanks in advance for any help!
MacBook, OS X El Capitan (10.11.6)