Your best bet is to build a Dockerfile for your app. We have limited support for Heroku provided buildpacks, but the third party buildpacks fail pretty often.
If you need to run two VMs for one app, the Fly.io way is to add a [processes] block to your fly.toml:
[processes]
worker = "python KexoBOT.py"
web = "python KexoBOTNews.py"