How to checkmate the opponent king with 2 bishops ?

STEP 1: First you need to gain control over the central squares (e4,d4,e5,d5) using bishops and control a1-h8 and h1-a8 diagonal.

STEP 2: Place your bishops in d4 and in e4

STEP 3: .Relocate your king from d1 to c5

STEP 4: Now move your bishops as shown with blue arrows to squeeze more space from the Black's King.

STEP 5: Repeat the Step 4 and squeeze more space from black's king

STEP 6: Move Your king from d6 to h6

Taking f8 square from the king and forcing to go in the corner.