On confession: it's a sacrament, and those who have not been initiated (been given their first confession) are not entitled to participate.
Using a screen would mess with the willing suspension of disbelief for the practicing Catholics out there, unless yours is a period piece. Every confessional I've been to since the seventies, small parish or large, now uses a curtain, unless it's really small, and then you're down to two chairs in the sacristy. But typically, you can kneel on the prie-dieu in front of the curtain for privacy, or go sit in the chair where you will have eye contact with the priest. And there's no way you would catch a glimpse of him. You would have to deliberately crane your head around the curtain, and then the priest would draw it back.
The opening is ritualized, and if a penitent doesn't follow it, the priest would ask if (s)he is Catholic. If not, he would likely schedule an appointment to meet with them outside the confessional.
Scheduled confessions typically run for a hour and a half or so on Saturday afternoons preceeding mass, in the church. But confessions can take place anywhere, and it is one of the solemn duties of a priest to perform confessions anytime if the penitent has great need of it. And it is usually a priest, not a bishop, simply because there are so many more priests and bishops have amazing amounts of admin work in their dioceses. But a bishop is not exempt from the stricture to provide confession when there is great need. One of my favorite stories about John Paul II is when he did this, and he was a pope. However, you would not expect to find bishops or popes sitting in the confessional on Saturday afternoons for scheduled confessions. That's really a parish priest sort of thing.
And the advice a priest gives tend to be very specific to the individual situation. I've never had a platitude thrown at me, although from time to time, Church thinkers and doctrine may be quoted. But again, this would be tailored to the situation. The point of the advice given at this time is to help this particular penitent avoid this sin in the future.
Hope this helps.