  The transition-metal-based kagome metals provide a versatile platform for
correlated topological phases hosting various electronic instabilities. While
superconductivity is rare in layered kagome compounds, its interplay with
nontrivial topology could offer an engaging space to realize exotic excitations
of quasiparticles. Here, we use scanning tunneling microscopy (STM) to study a
newly discovered Z$_2$ topological kagome metal CsV$_3$Sb$_5$ with a
superconducting ground state. We observe charge modulation associated with the
opening of an energy gap near the Fermi level. When across single-unit-cell
surface step edges, the intensity of this charge modulation exhibits a
{\pi}-phase shift, suggesting a three-dimensional 2$\times$2$\times$2 charge
density wave ordering. Interestingly, a robust zero-bias conductance peak is
observed inside the superconducting vortex core on the Cs 2$\times$2 surfaces
that does not split in a large distance when moving away from the vortex
center, resembling the Majorana bound states arising from the superconducting
Dirac surface states in Bi$_2$Te$_3$/NbSe$_2$ heterostructures. Our findings
establish CsV$_3$Sb$_5$ as a promising candidate for realizing exotic
excitations at the confluence of nontrivial lattice geometry, topology and
multiple electronic orders.
