@Arleen_Lasleur: You can define in Krita under ‘‘Settings’’ >> ‘‘Configure Krita’’ >> ‘‘Canvas-only Settings’’ which parts of the user interface should be hidden in canvas-only mode or not, unfortunately not for standard mode. If you now create a workspace with the dockers you need in canvas-only mode and save the workspace, you can select it before switching to canvas-only mode. To create and manage the workspaces, the icon at the right end of the toolbar is responsible (if you haven’t removed it, but you’ll find it also in ‘‘Window’’ >> ‘‘Workspace’’ >> ‘‘New Workspace…’’).
There is a plugin exactly for that, called “Krita-UI-Redesign” which is very useful, and I always use it, both in canvas-only and standard mode, with it, you can show and hide both the Toolbox and Tool Options Docker in the canvas at any time. So it’s good for freeing up space when you need it, and having Toolbox as well as Tool Options Docker at your fingertips whenever you need them. A picture of what it looks like in my case when in canvas-only mode can be found here:
The plugin is featured here (but also briefly mentioned by me in my post linked above along with another huge space saver (and tool ‘‘provider’’) “Kanvas Buddy”, maybe you read the whole post?):
And for your color question, maybe you find “Buli Notes” or “TF Easy Colors Map” useful?