Withdrawals are not available on any account that is currently in the evaluation stage. Evaluations exist solely for assessment purposes, and their balances consist of simulated capital that is never paid out. Only accounts that have transitioned to the funded stage are eligible for withdrawals.
Profit made during an evaluation does not carry over to your funded account either — the funded account starts at the original size of the evaluation. See Evaluation Period & Funded Account Activation.
If you hold multiple accounts, withdrawal eligibility applies per account, depending on which stage each account is in. An active funded account can be withdrawn from at the same time as a separate evaluation is running.
For the full rules that apply once you are funded, see Withdrawal Rules.