What should I do regarding the emission of gas and white fluid that sometimes recurs during prayer, knowing that the frequency of their emission has recently decreased?

The emission of wind invalidates ablution. If it stops for a time sufficient for ablution and prayer, then it is not considered سلس ( سلس refers to a continuous flow or discharge, like incontinence), and its presence invalidates ablution and prayer. The ruling regarding the emission of wind also applies to the white discharge (vaginal moisture), as it invalidates ablution because it exits from one of the two private parts, whether it is little or much, pure or impure.