ANSWER:

You can’t go back to the tashahud after standing up for the 3rd rakah.

Simply offer sujood assahu before salam. 

If, after standing up for a third rakhat I think that I have not read tashahud or that I missed second prostration shall I go back to sitting position and read tashahud/ perform prostration . Or I carry on my salat and do two prostrations of forgetfulness before the Salam.

Prayer | March 24, 2022 5:19 pm
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I use onion water for my hair treatment, i wash it properly with shampo though i smell of onion sometimes. Will my prayers be valid?
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Sheikh if incase a man missed the prayer in jamah maybe because of answering natures call or any other stuff like reached home that time etc in that case is it better if he prays at home the fard or he must go to mosque and pray there alone