Your questions are quite broad, so I'll just start with some basics.
You want to fly from somewhere in Northern California to Europe, in business class. Well, that shouldn't be difficult, though it will be expensive (business class is), and you'll need to set expectations appropriately.
What's the nearest airport to you with commercial air service?
Most folks prefer (but not everyone is willing to pay for) a non-stop flight. To minimize your time in transit and keep things simple, you are probably going to want to fly via SFO to someplace in Europe (nonstop). If SFO isn't a convenient departure point, you can depart from a smaller airport and connect in SFO, but that adds a stop, MAY add cost, but (perhaps) most significantly, you won't find a real "business class" experience on a short regional flight (smaller planes, domestic...neither have exceptional seats).
You may need to add a connection in Europe, too. That could mean one connection and short flight on a non-impressive plane in a seat that isn't super luxurious; again, the connecting flights are short so are easier to "tough out" in a lesser seat.
If it were me, I'd look for a flight from SFO, nonstop, in a nice comfy business class seat (all business class seats are not equal! - see below) to someplace near your destination (or as close as you can get to it).
The quality of seats on a "business class" ticket can vary tremendously. You need to check carefully what kind of seat you are getting on your specific flight. "Good" business class seats feature a spacious, comfortable individual seat that converts to a flat bed (parts of the flat bed may be a slight bit narrow, eg the foot well may feel more constrained than a night in your bed at home, but it's still so much nicer than coach). Many folks find that European airlines offer better food and service (debatable, often but not always true) than the legacy US airlines. Just make sure the specific seat on your specific flight is one of the good ones (for example, United has some old, disappointing business class seats on some flights, and some new pretty good ones on other flights - so you must check the specific flight/aircraft). Note that you can buy a business class ticket, but any connecting flights will have lesser seats: domestic (US) connections will be in "domestic First" which is generally just a modestly bigger seat; "business class" seats on most intra-European segments are just coach seats with the middle seat (in a row of 3) "blocked" so it's empty. The connecting flights would be short so I don't sweat the details on those. You want to focus your efforts and attention on the long flight (from California to Europe will be roughly 10-11 hours, so that's the flight where the extra comfy seat/bed will make all the difference).
Hope that helps get you started. Good luck.