This is a great question and very useful for real world navigation (though perhaps more sophisticated navigation tools and/or GPS may be used).
The wording "bearing of 340° from point A" means we'll place the protractor's center at point A, as shown in the 1st diagram you provided.
The bearing angles are a bit strange if you aren't used to them. 0 degrees, aka 000°, points directly north. Then 90 degrees, aka 090°, points directly east. Then 180° points south and finally 270° points west. Things wrap back around when 360° points north (though we typically don't use 360 and go back to 0 or 000). The bearing angles increase as you rotate clockwise.
Since 340 is between 270 and 360, it means the bearing is aimed toward the northwest. The gap from 270 to 340 is 340-270 = 70 degrees. Meaning that we first look directly west (bearing 270°) and then rotate another 70° northward to arrive at the target we want.
So we need to aim for 90+70 = 160 on the protractor in the northwest direction.
Check out figure 1 shown below.
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Now move the protractor to point B as shown in the 2nd screenshot you provided.
The wording "bearing of 245° from point B" means we place ourselves at point B, look north, and rotate 245° clockwise until aiming at the proper direction. We'll be facing the southwest direction since 245 is between 180 and 270.
The gap from 245 to 270 is 270-245 = 25 degrees.
So we'll start at 270 and rotate 25 degrees south. The marker we want to aim for on the protractor is 90-25 = 65 in the southwest direction.
Check out figure 2 shown below.
Refer to figure 1 (previous section) to see how I formed the black arrow that originates from point A. The blue arrow from point B is brand new.
The two rays intersect where the boat is located. This is where to place the X.
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Unfortunately I cannot answer part (b) since the protractor isn't lined up with P as the center. But I have a feeling you can move the protractor around maybe. If so then give it a try using the explanation I mentioned earlier. If you have questions, then please let me know.