If you were actively engaged in the business in 2018, you should be able to sell the assets and recapture the depreciation in the step by step interview for the farm business. This assumes you have the assets entered under the farm and have been depreciating them under the farm. If you did no farm business n 2018, you would have to use the 4797 directly.
In the interview, you would check that you sold the farm on a screen listing some choices for information about the farm. Later on, you'll be shown a summary of all your assets and you would edit each asset to enter sale information.