To internally transfer cash on the platform you will first need to navigate to the relevant client’s account and select Internal movement in the account menu.
Here you can select the source and destination accounts, you can instruct an auto disinvestment if required, and you can select how to invest the funds.
You can transfer cash between pretty much all account types on platform. The only exception to this is transferring cash between SIPP Drawdown accounts that belong to different groups. See here for more details on this.
You can find the full Process Guide here: