If you want the full version and license for commercial use,
you can purchase here :

https://staircaselab.com/product/california-signature-font-duo/

File Font Version : 

1. California Signature Duo.otf
2. California Signature Duo.ttf
3. California Signature Duo.woff
4. California Signature Duo Italic.otf
5. California Signature Duo Italic.ttf
6. California Signature Duo Italic.woff
7. California Signature Italic Script.otf
8. California Signature Italic Script.ttf
9. California Signature Italic Script.woff
10. California Signature Script.otf
11. California Signature Script.ttf
12. California Signature Script.woff