Equipment purchases made in 2023 that were not used until you started your business in 2024 would be listed as assets and depreciated. When you do this it will ask when you purchased it and when you put it into use. Depending on the type of asset you may be able to use a safe harbor election.
Business assets are found in the business income and expense section Below the Business expenses. You can also enter assets in the search bar and select jump to.
If these are supplies and not depreciable assets, then you need to select that your business is just starting and you will enter these under start up costs.