First of all, make sure you have an iPad that is compatible with Logitech Combo Touch. Logitech Combo Touch works with the following iPad models:
- iPad 7th gen A2197 A2198 A2200
- iPad Air 3rd gen A2152 A2123 A2153 A2154
- iPad Pro 10.5 A1701 A1709
Then update iOS to the latest version — iPadOS 13.4. Connect keyboard with the iPad using the Smart Connector and you're ready to go.