Hi, I am from canada and made $300,000 in profits from Bitcoin but it says my taxable income is only $150,000 and balance owed is only $46,000. Why is it so little?

Your Bitcoin profits are considered to be either Capital Gains or Self-employment activities (depending on your particular situation). SInce Capital Gains are taxed at a rate of 50%, you'll only pay tax on half of your profits.