Poland passport holders need a visa to enter Sao Tome and Principe. You must apply at the Sao Tome and Principe embassy or consulate before traveling. Processing times vary but typically range from 5-15 business days.
A confirmed flight reservation is usually required as part of your visa application documents. Rather than purchasing a non-refundable ticket, you can generate a free dummy ticket from MyJet24 to include with your Sao Tome and Principe visa application.