This research investigates the dynamics of the formation of bubbles and their behavior in microchannels, with a focus on understanding the factors that influence bubble generation, manipulation, and size control on a microscale. Numerical simulations using ANSYS Fluent were employed to explore the effects of microchannel geometry, flow rates, and surface properties on bubble formation. The study highlights the significance of capillary forces in determining bubble dynamics, offering deeper insights into the underlying physical mechanisms. Particular attention is given to bubble actions in a microfluidic T-junction with a constricted region, where the influence of two-phase flow ratio and capillary number on bubble generation patterns and size distributions is examined. Additionally, the research aims to develop strategies for optimizing the design of junctions with constrictions, targeting enhanced flow control and improved precision in microfluidic applications. These findings contribute to a better understanding of microbubble dynamics and offer practical guidance for the design of efficient microfluidic devices.