This part of the readme may answer your questions :
# List your VMs
flint vm list --all
# Launch a new Ubuntu VM named 'web-01'
flint launch ubuntu-24.04 --name web-01
# SSH directly into your new VM
flint ssh web-01
# Create a template from your configured VM
flint snapshot create web-01 --tag baseline-setup
# Launch a clone from your new template
flint launch --from web-01 --name web-02