This is a step by step document to help you setup unlocking LUKS partition with Clevis. However, Arch Linux Wiki details the built in support for unlocking LUCS without requiring Clevis but the steps are not entirely cleaar.
Step 1: Install Clevis packages and refresh the TPM permissions
$ sudo -i
# apt install clevis clevis-tpm2 clevis-luks clevis-udisks2 clevis-systemd clevis-initramfs -y
# udevadm trigger