Is it permissible for me to pray in congregation with a group of young men at home instead of going to the mosque, which is about 500 meters away, given that I do not own a car and the number of worshippers in the mosque is small?

If the distance allows for hearing the Adhan in the traditional manner (without a loudspeaker), then one should go to the mosque to perform congregational prayer, for its reward and the reward of striving to reach it, and because many jurists consider it obligatory for those who hear the call. However, if the distance is far and the call cannot be heard, then there is no harm in praying at home.