Does one have to repeat ablution and prayer if gas or anything else is discharged after ablution and before or during prayer, knowing that there is incontinence due to paralysis?

You are in the same ruling as one afflicted with سلس [incontinence/constant discharge]. Therefore, perform ablution for prayer after its time has begun, and pray with that ablution whatever obligatory and supererogatory prayers you wish until that time exits. What exits from you after or during ablution will not harm you, as long as you do not know a specific time when the discharge stops. You are not required to repeat the prayers after the time has exited.