Drive past him quickly and just ignore him for now. You will see the flood gate ahead close with a soldier on the outside shooting at you. Get back in the boat and drive out to the end.
Grab the health and energy as well as some ammo for the Magnum which you’ll get in a second. Pull the two concrete blocks out of the one basket to make the other fall. Stop at the little pulley system and notice the supplies out of reach. The path straight ahead is blocked so stick to the right.
