How do I make all my fonts available in a desig...

I have recently bought a new Mac air and a Silhouette Cameo 3 and am learning both systems, so I could use some help!

I would like to download fonts to use with my Silhouette software and am not having luck. I believe I've got some downloaded on the the computer but would really like to be accessing them in my Silhouette design space. How do I make that happen?

Thanks in advance for any guidance you may have