Major sins

Sallam 'Alaikum learned brothers/sisters, I live in a country where there are no Islamic (non-riba)financial systems and have a small start-up business of my own that typically requires funding. I currently have an interest paying loan and wish to return it due to the grave consequences of riba.However there are no alternative halal sources. What do I do? will Allah punish me should I continue to use interest money or are there exceptions where no other sources exist? I also have no other source of livelihood... Jaza'akallah Khairan.

Dear scholars, As-Salamu `alaykum. I understand that all the sins fall under two categories, minor and major. Is the method of repentance the same for both types of sins? Also, what if you happened to commit a sin but you did not know that the sin is considered major in Islam? For example, hugging a member of opposite sex falls under zina but the person did not know that before; is it considered just as severe? I would appreciate if you would provide me with the answers to these questions. Jazakum Allah khayran.

Dear sheikh, As-Salamu `Alaykum. After Shirk (association of partners with Allah) is there any specific order in which the sins fall? If so, what is the second major sin?

On this issue, we would like to quote Sheikh Ahmad Kutty, an Islamic scholar who states: Since Allah’s laws are solely intended to save humanity from the destructive nature of the evil inclinations inherent in our souls, He has declared certain acts as enormous sins because of their extremely disastrous consequences and effects on individuals

What are the major sins in Islam?