ANSWER: 

If he believes in amulets, you must not pray behind him! Look for another masjid that follows the correct Aqeedah or pray in a second congregation behind someone who has a correct Aqeedah.
Kindly refer to the following link(s):

Is it allowed to pray behind a Imam Who Believes On Amulets ( Tawez) That they can help ? Can I pray at home bcz the imam or of masjid believe on amulets

Prayer | February 14, 2018 8:34 am
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Sheikh there is a masjid near my house which is based on hanafi school of thought and asr prayer is prayed late. The starting time of asr is 3:22 and the congregation prayer time is 4:30 and there is also a masjid which is farther than this but i can go easily on car or bike. In that masjid time is 3:45. So which i should preferred to go? 1) for asr 2) and all other prayers
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I got a question about reciting quran during my salah. I am learing some surahs but do i have to recite the whole surah or can i stop anywhere i want.