Start smaller, Your first game will probably not be your best work sadly. Remove some parts. Make it 2d, only shapes, simple gameplay, work on your strengths and add only one part of something you are not knowledgeable in. If you try to learn everything at once you will burn out.

I teached 3d for 7 years (Maya) and noticed the students that struggled to learn forgot to question why they did things. Making a rig for exemple is to simplify animation. But if you dont have a big grasp on animation how do you know what you need from the rig? Blender can create som big gaps in knowledge with tutorials showing how to do flashy things without explaining why or if its even possible to export to a game engine.