Step 1:
Spend about 2-6 months learning and practising LUA code specifically for Teardown.

Step 2:
Figure out how to render 3D objects using the UI commands Teardown provides.

Step 3a:
Program and create the game with all the graphics, sounds, gameplay and story which should take about a year of solid work with a team of other programmers and artists.

Step 3b:
Realise that the game can't run well because it is just a mod that can only use the CPU to draw things and not the GPU.

Step 4:
Upload that 160 Gigabyte laggy monstrosity to the workshop

Step 5:
Realise what you've done and regret that you've wasted a year and a half working on a Teardown mod that you do not financially profit from.

Step 6:
Cry, but at least you have a lot of experience of writing in LUA. But also realise that all the other game engines use other, better programming languages like C#, HLSL, etc.

Step 7: Recover the file from the trash and try to sell it on the deep web as the new gta 6 which you need a ryzen 35 (the cpu of the servers of the future)

Step 8: realizing that you are stupid because rockstar has already released gta 8 and remastered gta 6 for ps9

step 9: you change the name to gta 10 remastered but since it is a 160 gb teardown mod you have to play it within teardown and apart from the fact that your rtx 4090++ is suffering from running gta 6 it also has to run the teardown so I know He doubles the work and explodes all over your face, he takes out your eye and moreover the gas in the kitchen was on so the explosion of the 4090++ made contact with the gas in the kitchen and you create a nuclear bomb that ends with your neighborhood and therefore with you and with your stupid cardboard gta 6 saved in a hdd

step 9b go to hell

step 10:being pushed by rockstar into a spiked coffin on top of a hill made of lava in hell