* A contract of business is signed between two people, one form Bangladesh and another form USA. Let’s assume that that the purpose of the contract is illegal in Bangladesh but legal in USA, then whether it will be contract or not?

I think if two people of different countries signed a contract, which is legal in one country but illegal in another country it will be a contract. Because when two parties from different countries enter into a contract, they are governed by international contract law unless they agree to abide by the laws of one of the countries. International contract law concerns the legal rules relating to cross-border agreements. It is frequently applied to international sales contracts. This type of contract law is broadly based on the idea of good faith and fair dealing in contracts. These principles are the basis of contract law in most jurisdictions. Good faith includes fair negotiations, an obligation to cooperate and good faith when terminating a contract. It also ensures that unfair contracts or deals are not enforced.
International sales contracts are governed by the United Nation Convention on Contracts for the International Sale of Goods from 1980. The convention was developed in the hopes of promoting international trade by developing a global set of rules for contracts. The convention is a compromise between legal systems of common law, civil law and socialist law.
One key element of international contract law includes the provision that the parties' nationality does not play any role when applying the law, thereby placing all parties on an equal playing field. Rules of the contracts are interpreted by what a reasonable person would consider fair and appropriate given the circumstances. International contract law is a branch of private international law, which relates to the cross-border dealings of individuals or