Is a Muslim who lives in Belgium sinful for opening a joint bank account with a government agency to deposit a rental security deposit, knowing that he cannot evade this procedure?

The basic principle is that it is impermissible to open an account in usurious banks, whether it is a current account or a savings account. However, if there is a dire need to open a current account for the purpose of renting a dwelling, then there is hopefully no harm in that. The account must be closed immediately once a way to do so becomes available.