Am I obligated to perform the obligatory prayers, and does the discharge of impurities and gas into the plastic bag nullify ablution? Can I attend congregational and Friday prayers, given that their discharge is involuntary and accompanied by sounds and odors?

What comes out of a hole in the abdomen requires detailed explanation: If the usual two exits are not blocked, then what comes out of the hole does not invalidate ablution according to the Malikis and the well-known opinion among the Shafi'is. However, if the two exits are blocked and the hole is below the stomach, then what comes out of it invalidates ablution. This is the madhhab of Abu Hanifa and Shafi'i. If the hole is above the stomach, the apparent meaning of the statements of the majority of scholars is that ablution is not invalidated in that case. Prayer is not waived for a Muslim as long as he is conscious and sane. Attending Friday prayer and congregational prayer is obligatory if possible, unless it leads to contaminating the mosque with impurities or harming the worshippers.