Hi @MelsBite
Please make sure all your apps in the Playstore and Galaxy Store are updated.
Then check in your Device and Battery Care in Swttings and tap on the optomise option, and then tap on Battery to see if any apps are excessively using your battery.
You can also > Clear Cache Files from the phone's System Partition Section > https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ You may need to insert your earphones or hook upto a powered On Laptop to access the Clear Partition Section. This may help with lag or stutters as this clears the phone of old/unused or broken cache files.There is also a Repair Apps option in the Menu System too.
I wish you all the best. 
