Personal I should construct this in Part Design. When using Part workbench you should realize that have to change several times to different workbenches. You already found out that you must use sketcher workbench. For making an array you must change to Draft workbench. I continued your design with m...

Change your first pocket to "Through all"

Still not enough information. Are you working in Draft, Part, Sketcher or Part design. Which version of Freecad are you using. Read the IMPORTANT information in the red banner

Welcome to the forum,
I played a bit and created a file I hope you can need. When making the Plane I had the solid toggled off and the sketch toggled on

Select the wall you want to use and make that the working plane. After that you place the window

In the pull down menu on top of the screen go to Edit, select Preferences and on the bottom the menu that pops up choose Reset

Welcome to the forum.
Freecad does not know what part of your sketch must be Padded.
Split your sketch in at least 2 sketches, first sketch of the handle and Pad that e.g. 3 mm
Next sketch of the wrench and Pad that e.g. 5 mm

At first: Welcome to the Freecad forum.
In your GIF I see that you close your sketch while a red warning is given about redundant constraints. Delete the redundant constraints and very often the problems are gone

It is easy to show the centre of the circles and arcs in Techdraw, just change the setting in View

Welcome to the Freecad forum.
It is in the Addon manager.
On top of the Addon manager is a tiny pulldown menu to change from Workbenches to Macro's.
Perhaps you did not see this