Create a Geo node and dive in, I’m using the test geometry for this, but use your own or an extruded font or something else that might be polygonal.
Next convert this to an OpenVDB Volume with the vdbfrompolygons node. For more detail in the VDB reduce the Voxel Size to increase the grid resolution.
Wire vdbfrompolygons into a vdbtospheres.
This will give you a low res version of your model made with a few spheres. To add more detail adjust the Max Spheres and Min Radius.
Uncheck Overlapping to see the model with perfect packing of spheres. Something so fascinating about this effect and it sure beats manually placing them all.. .