Check if there is viruses in ur phone Try to delete some files in the storage that might reduce the phones speed The last option might be to go and buy a new one

Format it nd it will be as good as new✌

First amarach restore madreg nw selkun

Format it and reduce the number of apps u used because as They are too many they decrease the processor speed that's why ur phone lags weym stack yemeyaregew