I am a 12 year old needing help on Mission Santa Clara?

If you want to use the internet you need to learn how to use the internet. Everybody uses google.com so you may as well use it too, just so everybody doesn't poke fun at you. You can search for "google advanced" to see what else it can do for you. For instance you can search a specific web site; you can search for a specific filetype. You can use images.google.com to search for a picture that looks like one you have. Then there is video.google.com which indexes much more than just youtube.

100 search engines: www.distancedegrees.com/2008/lose-your-wikipedia-crutch-100-places-to-go-for-good-answers-online/
Google tricks: www.johntedesco.net/blog/2012/06/21/how-to-solve-impossible-problems-daniel-russells-awesome-google-search-techniques/
Google advanced: mentalfloss.com/article/66425/how-get-most-out-your-google-searches

Answer to your question:
www.google.com/search?q=Mission+Santa+Clara+history