Mission 1: Osiris
This intel is at the very beginning of the game. When the opening cutscene is over, simply run over to the right after you touchdown and it will be on a dead grunt located in between two Covenant containers.
After you break through the icicle wall with the new Spartan Charge ability, stick to the left side until you see a small ledge that you can jump onto. The data pad will be there next to a dead Covenant.
When you enter the first large area (you’ll be able to tell by the size and the amount of fighting going on in the distance), you’ll want to stick to the right side of the map, hopping on ledges as you go. You’ll eventually see a stacked set of rock pillars that you’ll have to jump over to. There should be a dead grunt and some weapons. On the ledge right above that grunt, there will be a data pad that you can collect.
After you pass the area that the Kraken was at, there will be a left path that you can take that leads into an icicle cavern. Walk along that path but stick to the right end of that path, keeping an eye on the ledges below as you’ll eventually see a small ledge that you can drop down with a dead grunt lying on it and a data pad that you can collect.
After clearing out the large battlefield with the turrets to the right, instead of proceeding through the door, go to where the turrets were. You should see another platform nearby that you can drop down to. Near the ledge of that platform should be another data pad.
This one is pretty simple. While proceeding through the mission inside, there will be a big window over to your right overlooking the battlefield with a bunch of aircraft flying around. Right by that window is another datapad.
Before you leave the final area. to the right of the exit is a ledge. Climb on that and then there should be another smaller ledge right above that. Right there will be the last piece of intel for Halo 5: Guardians Mission 1: Osiris.