Does f5 has caching even though it has LTM/LC modules only

Yes, it does. See this SOL for details. It might be useful to deploy compression too, but the compression throughput is probably limited by your license. You can display the license with "tmsh show sys license" or on the GUI. There you'll find "RAM cache" as feature of your LTM base license (at least if you are on V11+) and also the level of compression that is included with your license (50mbps if you didn't insert some extra coins).