(N/A) In $SF_6$,the central sulfur atom $(S)$ has an atomic number of $16$ and an electronic configuration of $[Ne] 3s^2 3p^4$.
In the ground state,$S$ has two unpaired electrons in the $3p$ orbitals.
To form $6$ bonds with $F$ atoms,$S$ undergoes excitation where one electron from the $3s$ orbital and one from the $3p$ orbital are promoted to the vacant $3d$ orbitals.
This results in $6$ unpaired electrons in the $3s, 3p,$ and $3d$ subshells.
These $6$ orbitals ($1$ $s$,$3$ $p$,and $2$ $d$) undergo $sp^3d^2$ hybridization to form $6$ equivalent $sp^3d^2$ hybrid orbitals.
These $6$ hybrid orbitals overlap with the $2p$ orbitals of $6$ fluorine atoms to form $6$ $S-F$ sigma bonds.
The geometry of $SF_6$ is octahedral,with all $S-F$ bond lengths being equal and bond angles of $90^{\circ}$.