The GPL allows you to use the software freely for any purpose and to make money from it. Extra restrictions apply for creating derivative work.
Making a video tutorial using the software is not creating derivative work of the software, therefore there are no extra restrictions from that point of view.
The only thing you technically do need permission for is for reproducing the artwork (splash screen, buttons, icons) because making a video tutorial which contains on-screen copies of said artwork is arguably derived work, in a somewhat strict sense.
There is no separate license file for any of the artwork in Code::Blocks that I am aware of, so according to semblance (being shipped as part of a project that as an entity is under GPL), one would have to assume them being under the GPL as well.
Which means you are free to make copies and free to make money as long as you comply with the terms of the GPL, e.g. provide the source code for any modifications and derivative works (that is, in the case of a youtube video, the original capture). Of course you can still get a separate license ("special permission") that removes these restrictions from the respective authors.
Most of the "bigger" icons and images including the 8.02 but excluding the 10.05 splash screen are either derived from public domain sources or created from scratch, and copyright by me. I herewith place these under a "I give a fuck" license for any kind of reproduction in videos.
The 10.05 splash screen was conceived by Felix Weiszig, known as "otaco" on this forum. You would need to ask Felix if your video shows the 10.05 splash screen.
Most of the "smaller" icons which are not of trivial nature (such as a bullet point or wedge) are borrowed from freedesktop.org if I recall correctly -- so you would need to ask the guys over there if you want to be super pedantic. Though I doubt anyone cares.
There might be other artwork that I do not know about.
