Kindly refer to the following link(s):
Does Mispronouncing Surah Fateha invalidate the Prayer (Salah)
Ruling on making pronunciation mistakes during Salah / Prayer | Sheikh Assim Al Hakeem
What to do if one makes a mistake while reciting Surah Fateha during prayer?
What is the correct way of reciting Surah Fateha in Salah / Prayer?
Difficulty pronouncing Raa ر in prayer, must he rectify this as it may change the meaning
Does saying Iyyaka Na'buduu with Madd change the meaning or invalidate the prayer?
Waswas in Wudu & Prayers, he keeps repeating the Ayahs, what to do?