I literally had to hunt down 4 helicopters spread across the map. I drove like 15 minutes to the first one, left my car and picked up the turret on the back to destroy it. Then I hunted the second one for a bit and managed to take it down. The supplies fell into the damn military base. I drove around it for 10 minutes until I managed to get in, got the supplies, then I stole a cargobob and flew away while being hunted by 2 buzzards. The engine was slowly dying but I kept flying it until it completely gave up on me, then I took a dive with the parachute. The buzzards finally managed to kill me. I respawned and got the supplies back, then blew one chopper up with my rocket launcher, but that was my only missile. Died again, respawned. The other chopper I managed to shoot down with my AR. I quickly got the supplies back, but there was only 1 minute left and I was 3 miles away from the finish. I tried.
Meanwhile, my team mates who should've helped me were killing each other.

2020 update: Online is garbage.

2021 update: Cayo Perico is pretty good.