In the Self-Employed sku, enter the laptop information by going to:
Assets used in business > click on blue button "Enter additions/dispositions"
Laptops would be in Class 10 and if the laptop was purchased after November 20, 2018, select if you want to claim the accelerated investment incentive. This basically allows you to claim a higher depreciation/expense in the first year.
For more asset classes: https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/sole-proprietorships-partners...