Audio logs are one of the collectibles you can find throughout the missions of Halo Infinite. There are three different types you can find; UNSC, Banished, and Spartan. There are a total of three audio logs that are found throughout the Foundation mission. Here is where you can find them.
The first audio log is given to you as part of the story. After you have collected The Weapon, you will come across a room with data for you to collect. Interacting with it will give you a cutscene. You will obtain the audio log after this cutscene.
The second audio log is found shortly after where you get the cutscene for the first one. After a little while, you will enter a larger blue room with two bridges that need to be constructed. After The Weapon constructs the second of the bridges, you will fight a group of Banished. Continue forward once the enemies are clear and you will spot the audio log next to the door leading out of this room.
Toward the end of the mission, you will need to search for a Power Seed to activate an elevator. You will enter another large blue room with a bunch of pylons on the floor and ceiling. The audio log is next to where you pick up the Power Seed.