Following a mazhab

Q: Do we really need to follow a Mazhab?If yes why didn't the Prophet (Sallallahu Alayhi Wasallam) or his companions not do so? My friends confused me with this points because I know that we cannot add anything to Islam unless it's told or practised by the prophet Muhammed (Sallallahu Alayhi Wasallam).

Taqdeer

Q: It it the belief of Ahlus Sunnah wal Jamah that Allah knows all what has happened, all that is happening, and all what will happen - it does not
befit His Majesty to not know. So could you kindly explain the meaning of this Hadith which the guest Mawlana mentioned in a Jumuah bayan but did not elaborate upon and which caused some confusion: "Nothing can change the Divine decree except du'aa".

Spotting after the haidh period

Q: My question for today is I did ghusul on 18th of May but from 23rd I am spotting blood and despite spotting blood I was still praying and on 26th I was fasting again despite spotting blood. I told one Muslim lady and she told me my fasting is makrooh so I had to open my fast. I didn't pray on the 26th till the 28th but I did ghusul and I am fasting on the 29th but in the morning again I spotted blood so I just wanted to know am I allowed to fast and pray despite blood spotting or not?

Halaala

Q: If a woman is divorced three times, I heard she can do halala with a third person and then return to her first husband (after completing the iddah). I know that it is not permissible to make halala a condition in the wedding contract, but it is permissible for her to informally agree with the man (the mohallil) to make halala (by speaking to him), without formally specifying it as a condition in the contract and without announcing it publically? The intention of both parties would be to make halalah so that the lady is able to resume her life with her former husband and reunite her with her family.

Braking one's oaths

Q: I took three different oaths at once in a desperate state of mind, but then I realised it was impossible for me to fulfil them. Now that I have broken them, can I fast three continuous days for every oath. I am not poor but I don't have any money of my own (not even pocket money) and my parents are not very religious, they are not willing to help me in paying for kaffara. Please guide me according to Sunni Hanafi ruling.