Yeah there are free voxel programs you can use such as MagicaVoxel, VoxelShop and StoneVox. These are voxel model makers and editors which has even if not all, the features of the paid-software counterparts. Two of which are community made (I think…) which can be found here on the forums .
MagicaVoxel
VoxelShop
https://blackflux.com/index.php
StoneVox 3D
Feel free to ask for help ! Everyone here is willing to help
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