Well, if you want to completely (from 0 to 100) make 3D model of the Items you have shown on your own you have to do the following:
First you have to gather reference pictures (if you have access to the Items then you can make them yourself put Items far from camera and zoom -I heard this way you can reduce perspectivation effect! so, you will end up with orthographic-like pictures)
If you want you can search the Item (on websites like https://sketchfab.com/features/free-3d-models ) download them (or the ones that are similar to your Items) and open them in 3D software of your choice and then recreate them on your own!
Theoretically you can only use MOI but practically you have to be an expert MOI user :-)
I recommend you to use both MOI and Blender! ( You can do magic if you combine these two together!)
If you have more questions feel free to ask (here there are numerous talented and expert people who can help you)
If this relatively simplistic example gets you going on your hemet, I and others can help walk you through getting the various pieces going for your helmet.
If you need full on tutorial about how to do things, i will have to bow out...
Just make piece by piece and get them put onto your helmet shape.
The mask can be a separate "nudge in the right direction later" .... Most of it is fairly simplistic stuff
For expediency, I just flattened the 3d helmet to get flow to perform. But the way I did it could be called "Bad practice" by making bad geometry. Just success due to simplicity.
I think using a "Sphere" would have been an incorrect starting point. Trying to get a "Base" for flow to match a "target" of sphere because a sphere is a "special type of geometry"
I think I would make my "Sphere" with a different command that would allow me to make my base with the same general structure.... (Or i could cut things in half and only work on half at a time and use the flatten. But I think there are "better" methods to go after...
There are other discussions here regarding this. but OP doesn't need to dive into this to get going....
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