How to make friends admin panel on bootstrap (etc.) with PHP?

Question

Angular

Good afternoon!
I write a little in php (the main profile is a webmaster / SEO specialist, I make websites), there was a need to make an admin panel for my scripts to be run by a third party.
General meaning:
There are a number of scripts-classes-parsers, etc. each of which has its own config, I just run many of them via ssh with variables and after execution I receive notifications. It is necessary to display all this in a web form.
Additional logic:
Scripts perform a specific task, roughly speaking 7 sequential steps, and human interaction is required at each stage. All this is within the framework of one "niche", and each user can have many niches. In each niche, you can move in parallel and perform each of the 7 consecutivesteps on the way to the finish line.
It is necessary to make the launch of the next step in "niche1" available after the previous one is completed, that is, it is visually displayed in the admin panel + the next step is unlocked.
1. How to make friends, for example, the admin panel on material bootstrap or altair.tzdthemes.com with my scripts?
How should they interact? I can add the backend part, but I need to understand how to do it "correctly", for example, make a separate table in mysql where I will write the status of each niche and % completion, but how to take it all to the level of .HTML files of the admin panel and template engine, in what format is better ? For graphs, the same json is needed.
2. What is the right way to set up a technical task for a freelancer (because I myself don’t want to dive into the topic of layout at all) so that it doesn’t turn out that he makes everything beautiful for me, only then I won’t be able to use all this beauty at all? There are examples?
3. I have already started to draw up a layout and a description of what I want to get approximately through mocap services (like ninjamockup / mockflow ), having previously drawn it on paper. Does it even make sense?

Start layout

4. And finally, where can you get it and find out how it all works and is friends with each other (well, just a finished project or something), I tried to find it - I don’t come across anything, like the TK I couldn’t even find a full-fledged one on the admin panel, the only thing what happened https://docs.google.com/spreadsheets/d/1qmsspnfxQm...
5. Admin templates, etc. - Is it so important which one to choose or is it enough just to switch them later? I want the code to be scalable and the author of the code to be easily replaceable, that is, something popular, or should I not pay attention to it? What is in the top in popularity now? Perhaps in the future I will expand the functionality. I want to take for example something from this https://wrapbootstrap.com/themes or https://themeforest.net/category/site-templates/ad...

Answer 1

If you don’t understand, then it’s obvious that you shouldn’t start with more mundane things :)
I also try to do this (order management from the site), and not very successfully, I have to write about a third of the questions here, and the rest can be googled. There is no ready-made guide for creating an admin panel, because it is always purely individual things.
There are already ready-made lessons that you can see for an example like here, the first link in Google .
Do you want a working example? Take any OpenSource CMS, for example one of the most popular - wordpress is open source. See how MVC and templating engines work, enjoy :)
And if specifically for your questions:
1. Everything is done through the backend and input and output, at the html level you only do markup.
2. Why give the layout of the admin panel to a freelancer, if there are already a bunch of ready-made free solutions, to which it remains only to attach the backend? Google "free admin template", there are dozens on the same bootstrap.
I use this
3. It has if you are going to make up on your own or through freelance.
4. Search badly, I already wrote about opensource above.
5. The admin template is purely your choice, there is no point in asking anything at all. There is no difficulty in the scalability of html / css code.