Hello,
I have recently started my work with this particular CMS system, and would like some information, what would be best way to start importing files to the CMS, as currently we have webpage that is only source code and some folders with images and other stuff.
Also how should be noted the parts in the main PHP files, that will be dynamic?
Thank you very much!
Hey @Janis_Anerauds
Welcome to MODX!
To get started you may want to check out a tutorial video series I’ve recently started working on, hopefully it’ll get you up to speed quickly - any feedback also appreciated.
Thank you very much! Will watch it, and then you will see if i still have questions, it wasn’t that good 
Thanks 
It’s still growing weekly so be sure to check the playlist for the other videos which may answer some more questions
Just to be clear about a couple things, you will need to make a template with your HTML structure in it. Bootstrap is a great way to start, it will give you a good look on many devices.
The you can put all your css in one file and link to it in the “head” portion of the html template.
PHP and other technologies can be used to do things within that structure, like perhaps a sidebar with latest posts or items or whatever, yes definitely dynamic
For any sort of tool you had on the old site, you will need to make a new one, but you can definitely import the data, like blog posts or news articles, or products. The Extras will get you started on that.
This article on porting your site to MODX is a little dated, but you might still find it helpful.
Welcome to MODX 
Guys, thank you very much! Now I got some really good understanding for this CMS system!