You need a visa for Guinea if you have a Spanish passport
Visa options for Guinea
Electronic visitor visa
Travellers need a visa to visit Guinea for Business or Tourism. A Guinea eVisa is the fastest and easiest way of obtaining a visa for Guinea because travellers can submit their application and supporting documents online. Once the application is approved, travellers receive their eVisa confirmation electronically. A valid visa is required to board the flight. If the visa is expired or doesn’t match the traveller’s passport information, travellers will not be able to board their flight.