[fen "8/8/5b2/5k2/8/3R4/4K3/8 w - - 0 1"]
In this endgame can white win ? If so what is the plan here for white or how sould black try to defend this position
This ending is drawn, and the main thing that Black needs to avoid, and which White should aim for, is having her king driven toward the a1 or h8 corner (the problem being that those squares are the color that the remaining bishop travels on). White cannot force Black into either of those corners from this position, and so it is drawn. To see that the others are "good" corners, note that in the following position Black need only keep shuffling the bishop along the b8-h2 diagonal, and White has no way to progress toward mate, as a rook check on the eighth rank can always be blocked safely (which isn't true in the "bad" corners).