Answered by Ustadh Tabraze Azam
Question: Am I suppose to choose two surahs to recite before takbir, or can you just recite whichever surah you want after the takbir?
Answer: Wa alaikum assalam wa rahmatullah
I pray that you are well, insha’Allah.
It is disliked (makruh) to fix specific surahs to recite during the obligatory (fard) prayer. For instance, always reciting Surah al-Dahr and Surah al-Sajdah during the Fajr prayer on Fridays as it indicates preferring part of the Qur’an at the exclusion of the rest.
However, this dislikeness is only if:
[1] You consider them to be necessary or,
[2] You are the imam and reciting them regularly may lead some people to regard their recitation as being necessary (wajib).
Otherwise, there is no harm in doing so.
[Ibn `Abidin, Radd al-Muhtar]
And Allah alone gives success.
Wassalam
Tabraze Azam
Checked & Approved by Faraz Rabbani