We have good news and bad news.
The bad news is that demo/paper trading accounts cannot be connected to
Capitalise.ai* as of yet.
*Except for Eightcap, ACY and Pepperstone demo MT4 accounts
However, and that's the good news, it does not matter.
Once you are signed up, you can backtest and simulate strategies without connecting an account at all (real/live or demo).
When you wish to connect your real account and trade live strategies, search for your broker's connection guide on our support center, and start trading live!