A data model is an organization of data elements representing real-world objects/things/people in our code. Every object and/or element in a data model represents one piece that we could create visual representations for in the DOM of a front-end application. Ultimately everything we see on the DOM is backed up by some piece in our data model.
A framework is a programming tool whose primary benefit is the ability to keep the UI in sync with the application's internal state. This is especially helpful for apps that require constant DOM manipulation from user inputs. Frameworks are different from libraries in terms of the rules they follow and what they call to. A framework can be seen as a "school" or "university" in which there are restrictive rules that must be followed. For instance, in order to make a call in a framework like Django it must be named as a template. And frameworks calls to your code (which in turn the code can to a library - maybe). Libraries, on the other hand, can be seen as your "home" in which there are less rules and more freedom to do things, especially with calling code wherever you like since you are calling to the library.
We should consider using a framework over vanilla JS because of the problems we as developers often run into with updating our UI/code on every state change. If we have an application whose UI is updated through DOM manipulation every time the user does something (such as entering a form or selecting a list), it requires lots of code to update each state change. This can result in extremely fragile code, especially if we need to sync the application with a server and compare date on each state change. If any mistake is made, no matter how minimal, the UI could potentially be out of sync from the data, causing all kinds of potential issues ranging from missing or incorrect user information, unresponsive application elements, and even triggering the wrong action/behavior.
Frameworks, in contrast, guarantees our UIs will be in sync with the internal state of the application (as long as we don't mess with the immutability of the state). Utilizing frameworks allows us to define the UI in a single shot, which then automatically updates it after a state change. This is accomplished by re-rendering the whole component, such as in React, through a process called reconciliation in which a virtual DOM is rendered and compared to the previous DOM snapshot, and any changes are calculated and executed to the real DOM.
Components standalone, independent parts of an application responsible for handling only a single UI element. They are similar to JavaScript functions in that they both accept inputs (called props in React, which stands are "properties") and return React elements describing what should appear in the application. Components are useful because they are modular and reusable pieces of code that can be snapped and connected together to create complete webpages/applications.
JSX is a syntax extension to JavaScript that describes what the UI should look like. It is a mix of JavaScript and XML that works to render appropriate HTML components, which is highlighted above.
React props, as mentioned earlier, are "properties" used to pass in arguments to components similar to functions. They are objects given from its parent component down to the child functional/class component and they should remain immutable.
A React state holds data representing the actual state of an application, which can be changed and mutated through user interaction. It is slightly different from props in that state holds data representing the state of our app and can be changed/mutated, whereas props remain immutable.
"Data down, actions up" in React is a phrase the describes the flow of information from parent to child components and vice versa. "Data down" refers to the passing of data and/or functions through props from parent to child components in order to render them in the DOM. "Action up" refers to the sending of data back up to the parent from the child component through an action/event, which are often connected to a callback function.