So you mean you’re limited by having to view the source of one block at a time?
If I understand you correctly there, if you hit the ellipsis in the top right corner of the whole editor (the three vertical dots), it has an option to switch the whole editor into code mode.
The reason you are seeing IDs and classes is because you are now given a direct representation of what will be on the front end of your site, so this should give you more control overall, but they can also be ignored if you don’t need to touch them.