Thank you for reaching out austy-austin, apologies for the inconvenience caused.
Please follow the troubleshooting steps below;
Ensure that your phone is running the latest software version. Go to Settings > Software update.
Clear app cache: Clear the cache for individual apps that are lagging. Go to Settings > Apps > select the app > Storage > Clear cache.
Clear system cache: Clear the system cache partition, which can help improve overall system performance. To do this, turn off your phone, then press and hold the Volume Up button, and Power button simultaneously until the Samsung logo appears. Use the volume buttons to navigate to "Wipe cache partition" and press the Power button to select it. After the process is complete, restart your phone.
Reduce animations: Go to Settings > About phone and tap on "Build number" seven times to enable Developer options. Then, go to Developer options > Window animation scale, Transition animation scale, and Animator duration scale, and set them to 0.5x or turn them off.
Limit background processes: Go to Settings > Developer options > Background process limit and select a lower limit.
Remove unnecessary apps: Uninstall apps that you no longer use to free up storage space and reduce the load on your phone's processor
Factory reset: If none of the above steps work, you may consider performing a factory reset. Make sure to back up your important data before doing this, as it will erase all data on your phone. Go to Settings > General management > Reset > Factory data reset.
Please also check your device storage as his may cause the device to lag
