Complex sentence: In Venezuela he will join the family's lithographic business and soon he will enter in contact with the most prominent artist and painters of the time, between the ones were Raúl Santana and Leoncio Martinez, the later founders of the Fine Arts Circle of Venezuela.
Split into simpler sentences: In Venezuela he joined the family's lithography business and soon he entered/got in contact with the most prominent artists and painters of the time. Here belong Raúl Santana and Leonico Martinez, the later founders of the Fine Arts Circle of Venezuela.