Finding the missing girl
Land at the Capitol Village. Start by going right and selling your old armor and Ancient Artifacts. Then continue right and talk to the chief. Select "How can I help?" then "I'll help." Go to the Jungle drop site. Climb down and fight the small yellow Spit Lizards running around below the ladder. Next, enter the cave and fight the two Big Dinos. Keep going left and then climb up. One last Big Dino will be guarding the lost girl. Talk to her and return to the chief for another task.
Collecting fruit
To avoid fighting, you can travel to Wiegre and buy some Fruits and Vegetables. To get them for free return to the Jungle. It should be just as you left it. Now, fight the Spit Lizards on the right. You will probably have to return to your ship to recharge ammunition and health. Collect all the fruit. If you don't find 15, you can go to the Capitol Village to train your crew while you wait for the Jungle to re-spawn, or you can just go to Wiegre for as many as you need.
Killing the large green beasts
You will have to wait for the Jungle to re-spawn before you can find them. While you are waiting, you should hire and arm another crewman at Anoa. You should also replace your Needle Pistols with Anoa Long Guns. Once the drop site re-spawns, land and cross the new bridge. Kill the Big Dinos from the level of their heads. Then fight the Spit Lizards. Recharge your ammunition and then fight the Giant Dino here. You will probably have to recharge your health due to the cramped space. After defeating the first Giant Dino, climb down the hill and fight the Spit Lizards as you did before. Then use the shoot-and-jump tactics to kill the second Giant Dino. Alternately, you can fight the lower Giant Dino first and then fight the upper one. Harvest all the Fruits and Vegetables. Return to the Capitol Village to get a Worry Doll and your next destination.