I am separated and I can only claim one dependent (I have three children 10-15 years old). Is this correct? Does this also apply for the Climate Tax Initiative?

[TurboTaxBrenda1]

Yes, The tax credit for an eligible dependant can only be claimed once. Each household is allowed only one claim for this amount, even if there is more than one dependant in the household.

You should enter all your children and other dependants when preparing your tax return to claim other dependant benefits that may be available.

TurboTax will calculate automatically the credit for Climate Action Incentive.