I understood the answer but still question remains in my mind that for eg I have faeces on my finger and I clean it with tissue, then whatever wet place i touched with the finger, it will be najis? I am not sure if there was still any transfer of smell or taste.

Please note that we can’t not clean faeces with tissue paper or clothe etc otherwise that surface will always remain Najis and wherever you touch and if it was wet then that surface will also become Najis. Cleaning faeces with tissue paper or cloth or clay etc is allowed only and only after using toilet and restricted to anal area not even if it has been spread out in other areas. Therefore other than anal area we have to use water to make that area Pak ( according to shuriat) even wet tissue can’t make it Pak while it will make bigger area.