3. When you use crypto coin to buy goods or services for example using Bitcoin to buy a car, tv, bicycle, etc. It is taxable and the tax is called income tax
Source?
You've paid the income tax in number 4, you will not need to pay income tax anymore when you spend Bitcoin.
If you live in a country where Bitcoin isn't legal as legal tender, but the companies accept Bitcoin payment, it means when you pay using Bitcoin, it will convert to fiat, in this case you will need to pay capital gain tax (if the amount you buy Bitcoin is lower than when you spend).
If you live in a country where Bitcoin is legal as legal tender,
I think you will not need to pay capital gain tax CMIIW.