Q: mac 10.11 ssd question

Run Apple Hardware Test/Diagnostics

http://support.apple.com/kb/TS2771

Can you successfully install and run El Capitan on;

- An internal rotating drive?

- On an external USB or Thunderbolt connected drive?

On external SSD?

You asked "What do you mean internal rotating drive?"

one that ratating disk vice an SSD.

So yo do not have an enclosure or adopter that will connect to an external SSD?