Income taxes - Summary of Income Tax Expense (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Oct. 31, 2021 |
Oct. 31, 2020 |
Oct. 31, 2019 |
|
| Income Taxes [Abstract] | |||
| Net loss | $ (226,559,288) | $ (9,275,962) | $ (4,100,782) |
| Statutory tax rates | 26.50% | 26.50% | 26.50% |
| Tax expense (income) at applicable tax rate | $ (60,038,210) | $ (2,458,130) | $ (1,086,707) |
| Change in unrecognized deferred tax amounts | 8,799,310 | 2,365,715 | 993,703 |
| Non-deductible item and others | 51,238,900 | 92,415 | 93,004 |
| Income tax expense | $ 0 | $ 0 | $ 0 |