You would enter the expenses on Line 9945. Line 9220 is for expenses that are not related to working from home, ex: you have a storefront or commercial unit, etc... which you pay expenses for. This Canada Revenue Agency (CRA) page has more information: Line 9220 – Utilities
Just remember not to include expenses related to your employment or your rental as part of your business. They go on you T777(S) and your T776.