This paper investigates the propagation of sub-Terahertz (THz) electromagnetic waves within an indoor environment using simulations. The study considers the directional and omnidirectional propagation characteristics and presents a statistical model; the model parameters were derived from ray tracing simulation in an indoor environment, including path loss exponents (PLE), delay spread, the number of clusters, the number of rays per cluster, the cluster power, the cluster and subpath power, intra and inter delay excess delay and the number of the direction of arrival spatial lobes at 245 GHz in both line-of-sight (LOS) and Non-LOS (NLOS) propagation scenarios. The Wireless InSite (WI) software was used for simulations using the shoot and bouncing rays (SBR) technique. The recorded received signal strength (RSS) and path loss (PL) are validated comparatively against WinProp software results using the dominant path model (DPM). A good agreement between the two techniques is demonstrated.