what is the molecular geometry surrounding the nitrogen atom in nf3?

In NF₃ molecule, the central N atom is attached to 3 N-F single bond and 1 lone pair of electrons, i.e. 4 electronic groups. According to VSEPR theory, the 4 electronic groups are arranged as tetrahedral as shown below.

In consideration of molecular geometry, the lone pair of electrons is neglected. Hence, the molecular geometry is trigonal pyramidal (or triangular pyramidal).