Would probably be better to post this to [r/ECE](/r/ECE) rather than to Hardware, but either way:
Shortly summarized: A MOSFET is a 3-terminal device (4 if counting bulk, and there's also a 6T type), where you have Gate, Drain & Source. Assuming you know BJTs, you can "map" them as:
If again, we're comparing MOSFETs to BJTs, we can say that a MOSFET is a VCCS (Voltage controlled current-source), while BJTs are CCCS (Current controlled current-source). In other words, when you apply a voltage to the gate of a MOSFET you'll create a current at the drain of the MOSFET. The current that's generated depends of the operating region:
Normally one operates in the the saturation region.
Not sure how much details you want, but if you want to read more about MOSFETs you've got books such as Sedra & Smith or Razavi
I can second Sedra & Smith. I used this in Electronics I/II courses for the 2018-2019 academic year, then several more times for other projects and references afterward because it has so much good information.
Microelectronic Circuits from Sedra/Smith for all things amplifier! Wonderful textbook. https://www.amazon.ca/Microelectronic-Circuits-Adel-Sedra/dp/0199339139/ref=sr_1_1?ie=UTF8&qid=1502291667&sr=8-1&keywords=sedra+smith
A lot of my professors put their video lectures on youtube now so those are a lot of great videos to watch, but I'm not sure on the rules of whether or not I'm supposed to share them so I can only link the ones that have public Youtube channels.
For Electronics (BJTs, MOSFETs, Feedback networks and things like that) you're gonna want to eiter download or buy a copy of this book (https://www.amazon.com/Microelectronic-Circuits-Electrical-Computer-Engineering/dp/0199339139). It's a pretty easy to follow text that is great for learning all the basics of micro electronics. Most universities use is so there are a lot of lectures using that text as reference.
For Digital systems (El E 235), and some useful Engineering matrix math and probability (Engr 310) on this channel: https://www.youtube.com/channel/UCf4G95tHQPnphwpfrkzelgA and https://www.youtube.com/user/OleMissVLSI (EL E 385 for computer architecture and the like)
For basic circuits this channel is good. https://www.youtube.com/user/RebelsLoveCircuits
Programming is best learned on codeacademy.com unless you want to learn C or something lower level, in which case i'm not too sure where to do that other than a course or reading a book online.
For your basic math and calculus you'll want https://www.youtube.com/user/patrickJMT (the real mvp) and Kahn Academy of course.
Then once you've gotten down the Laplace Transforms and understand the Laplace domain and Frequency domains, you can go onto my favourite topic in El E which is control theory. For that you're gonna want: https://www.youtube.com/watchv=oBc_BHxw78s&list=PLUMWjy5jgHK1NC52DXXrriwihVrYZKqjk.
I'm not really sure what else there is, but If you can think of any specific topic I can try to find the best material I remember using.
That's a common source amplifier.
https://en.m.wikipedia.org/wiki/Common_source
I'd suggest checking out Sedra and Smith on microelectronics