You can claim for home office expenses if you are eligible to deduct and meet the eligibility criteria. Only costs paid for your workspace in your home can be claimed. Part of your costs related to your workspaces such as Water, Heating, and Electricity can be deducted if you have not paid these for your personal unit.
For more information, you can use this link to check the expenses that you can claim: Expenses you can claim
You can also refer to the calculation schedule given by the CRA (Canada Revenue Agency) in detail.