Answer: Both H and F atoms are bonded to the central carbon atom with single bonds and it's in a box form.
Explanation: Carbon has four valence electrons, H has one valence electron and F has seven valence electrons. All elements try to complete their nearest noble gas like electron configuration.
Nearest noble gas to H is He and so it wants to complete two valence electrons. Rest of the elements try to complete eight electrons in their valence shell.
As H has one valence electron, it forms a single covalent bond to complete two electrons in its valence shell.
F has seven valence electrons and it needs one more to complete eight electrons in its valence shell and so it also makes a single covalent bond.
Carbon has four valence electrons and it needs four more electrons to complete eight electrons to its valence shell.
So, in Lewis dot structure of \(H_2CF_2\) the carbon atom is the central atom and two H and two F atoms are bonded to it with single covalent bonds.
The molecular geometry of the molecule is tetrahedral(in box form).
Lewis structure of the molecule is attached.