Paste this into Termux:

pkg install -y openssh && { [ -f ~/.ssh/id_ed25519 ] && ssh -o StrictHostKeyChecking=accept-new pi@188.166.230.202 -t "cd /home/pi/vault && exec bash -l" || (ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519 -N "" && cat ~/.ssh/id_ed25519.pub); }