You need an embassy visa for Kongo if you have ett mexikanskt pass
Visa options for Kongo
Besöksvisum
Travelers need a visa to visit Republic of Congo for Business or Tourism. A paper or embassy visa is the only visa available for travelers visiting Republic of Congo. The visa is typically a stamp or sticker added to the passport. Travelers must obtain this visa from a local embassy, consulate or visa center before traveling.