In QB online how do I record a vehicle purchased for cash?

The vehicle is a Fixed Asset.

The source of purchase is Cash from Cash on Hand banking type account. How you secured the "cash" is a separate issue.

Maybe you mean a paper check from checking account instead.

"+", Vendors, Write Check.

In detail enter the account you create for this specific Fixed Asset. Name the vehicle as the account. It can only be expensed through depreciation schedule and reported on Form 4562 and then as Depreciation Expense against Accumulated Depreciation but that doe snot happen for 10 more months

The account is the new Fixed Asset account you create to track the value of the vehicle. Vehicle purchases are subject to cost recovery by depreciation over time instead of up front expense.

There are from time to time programs for accelerated or up front depreciation but that is only used at tax time. For now it is a fixed asset