No, you cannot. Vietnam visa on arrival is applicable to air travel only since the visa applicants must get visa stamped at the arrival airport in Vietnam. If this is the case, you are recommended to contact the most convenient Vietnam Embassy/Consulate to apply for a visa.
Can I use Vietnam visa on arrival for my entry by land or sea?
Vietnam Visa India - About Visa on Arrival - Can I use Vietnam visa on arrival for my entry by land or sea?