[COGlory]

Diffusion is typically passive, sometimes (rarely) guided. But actual genome delivery usually requires energy stored in the capsid. For membraneous viruses, it's usually energy stored in the spike/fusion protein, plus some help from the host.

Note: I'm talking about energy stored in the 3D structure, not ATP molecules.

[alyx]

Where does the energy stored in the 3D structure come from? How does it get infused with said energy?

[COGlory]

When the virus is made by the previous cell, as the virus is assembled, it is assembled into what is called a "metastable" state. This is a low, but not lowest energy state, or energy well. Typically the lowest possible energy state requires some additional input of energy to reach (it has to get over a small hump to find the deepest well). That energy often comes from an interaction with a new host.