I'd like to achieve something similar to this diagram using d3:
https://gojs.net/latest/samples/records.html
I was trying to look it up on the web but I hardly found any resources to get started with.
I'm quite new to d3 so I don't know how to approach this task, any help or guidance would be appreciated!
This is another one of those questions where people need to implement a sophisticated diagram visualization and they think just because D3 is a lot about visualization, it will be a good fit.
IMHO it is not.
D3 could be a part of the solution, but it certainly cannot be the solution alone: It's almost like asking whether JavaScript can be used to create this kind of diagram. Of course it can! D3 is just a very thin (but very useful) layer on top of the DOM+JavaScript, that can help you with crunching numbers, work with colors, coordinate systems, create DOM elements, and simplifies working with the DOM. Think of it as jquery for DOM and data plus a lot of very nice demos. But the value very often is in the demos, rather than in D3 itself: You need to implement a lot of things to get from a simple mapping from data to dom elements to a sophisticated diagram visualization like the one you are referring to.
If you don't want to implement and maintain most of the low-level diagram logic yourself, you should rather be looking at a diagramming solution, rather than a tool that will help you create SVG elements elegantly with less code.
Look at this question to see a list of graph and diagram visualization software. Agreed, D3 is also on this list (for the same reason you are asking this question), but there are also far more capable tools on that list that you should be looking at, my recommendation being either the one that you've found already or preferrably this one if your requirements are more sophisticated.