@aryobarzan
On the interest rate, and why it should be adjusted according to inflation, I would like to add two points.
First of all, interest rate is not like creating money without work. It is simply paying depositor's own money back in its present value, and usually not even in full. So, in fact, not only the depositor is not gaining anything, but he/she is losing capital as well.
Secondly, if you do not pay a high enough interest rate, which should be close to the inflation rate, people will do a simple calculation and realize that their money is vanishing into thin air when you invest it in banks. So, they pull their money out of banks and instead invest their money in things that will retain their value over time. Like what? In case of Iran, popular choices are the US Dollar, gold, silver, real estate, stock market, cryptocurrencies, foreign real-estate or foreign-made goods, or goods that retain value like cement, sheep, pharmaceuticals, etc.
Do you see what happens? By not collecting money in the hands of the people, people who have money will either invest their money in things that the government cannot directly control (like the US dollar or gold), leading to devaluation of the national currency as we are witnessing, or they will buy goods that can greatly affect the lives of others and will increase the costs of living for everyone, leading to more inflation.
When prices tend to go up continuously, people start hoarding necessity goods to sell them at a higher price in future. Inflation will go up even more. The government will be forced to increase salaries, which again will add to inflation. Your economy will enter a vicious circle caused by uncontrolled liquidity.
However, if you increase the interest rate and make it close to the inflation rate, people will have an incentive to put their money in banks because unlike most other options, banks are guaranteed to pay what they say and depositing has a minimum risk (and you can always instantly withdraw your money from your account at any time you want). Risk-averse rich people who are not looking for trouble and just want to ensure that they can live comfortably until death, or people who are so rich that do not care much for getting richer, would deposit their money in banks again. The central government can then use this money to pay its internal debt (without printing more money) or invest it in national projects (without printing more money) or pay it as loans to entrepreneurs and businesses. Hoarding will hopefully stop. Deposited money will re-enter the economy through controlled channels and the government will have a better control over who gets to spend what. Money laundering and tax evasion will be more difficult. Inflation will eventually stop growing like crazy and the value of your national currency will not collapse like it is now.
After you have increased interest rate to a number close to the long-term average of inflation rate, you need to reform your loan system and your tax system. Loans should be paid to people who can initiate new business ideas. This should be different from startup accelerators that usually invest in only few ideas. Currently, banks do not have specific loans for new businesses or entrepreneurs. They give you loans to buy Iranian cars, to buy Iranian-made home appliances, to renovate your house or to construct a new house, but they do not give you loans for starting a new business!
On the other hand, because loan interest rate is low, there is an arbitrage that encourages people with power to use their resources to get even more loans and milk the banking system dry. This means that the rich will become richer and the poor will become poorer. There are thousands or maybe even millions of people who absolutely do not need loans, but they take them as often as they can only because they can and it is profitable in long-term.
The only way that the Iranian economy can be saved is if we gradually increase bank interest rates to near the inflation rate, or else the economy will go down the toilet more than now.