The way the game works is you need to move towards the big rock ahead, look at it, get close to it until you see a red square at the top of the rock. Then, press the Grapple key to grapple on the rock. Then, you need to look at the branch above the rock and look for a red circle that will tell you to swing on it. Press the Swing key and you can jump to the next area. The next area was meant to make a connection from the power cable to the generator to connect it to the door so that it can be opened.