For a web developer these days, it's essential to know JavaScript, HTML, and CSS. So, my advice would be to begin your journey there, from the good old trio.
Start with the HTML, then learn CSS selectors and how to style the document, and afterward go for JavaScript and dynamic DOM manipulation. Check out this post after reading this comment. A great source with a lot of documentation is the official MDN website.
For the server side, I would recommend .NET and C# since the syntax is similar to JavaScript (TypeScript especially, but don't worry about this now), therefore, you will not write your server-side code in a totally different way. If you choose PHP, for example, it will look and feel totally different. Also, Node.js plays a significant role in web development these days, so the knowledge about it and the ecosystem around it is a big, if not the biggest, plus. It all depends on the app you are developing. Complex applications, like enterprise level, would have a really hard time operating only based on JavaScript.
Of course, some basic programming knowledge is required. You need to be familiar with concepts like iterations, sequences, conditionals...No one will care if you know who invented the programming and who created React, and yet you don't know to write a for loop. So focus on practical knowledge. If you learn something the practical way, the theory will be easier to understand later on.
Differentiating the primitive data types like string, int, boolean...is also required. After mastering those, array and list manipulation would be the next step and after, you can start thinking the OOP (Object Oriented Programming) way.
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OOP changes your way of thinking, and you are shifting on the question What instead of How, you stop writing conditionals and start using polymorphism and inheritance, but you shouldn't worry about this right now. It's the next level of you as a developer.
After completing all the above you can start thinking about the frameworks and libraries. I would recommend Vue since, in my opinion, it's the easiest one to learn by someone who is a beginner. But don't be mistaken, if it's easy to learn, it doesn't mean that it's less powerful and featureless comparing with React or Angular.
I would not recommend Angular since it's based on TypeScript and you shouldn't learn it before you learn JavaScript. TypeScript is a programming language, s superset of JavaScript which enforces the static typing. You can leave it for the very end of your learning journey.
Regarding IDEs (software to use to develop your app), I would recommend Visual Studio CODE.
So, your milestones would be something like:
After your for loop of the above stuff ends, you can start learning some advanced concepts like OOP, SOLID principles and functional programming.
Best regards.