Complex sentence: He was trained by the Jesuits, shortly before their expulsion, and attended the Colegio Real de San Carlos and his cousin, Manuel Belgrano, secured him a position in the public administration in the Viceroyalty of the Rio de la Plata.
Split into simpler sentences: He was trained by the Jesuits, shortly before their expulsion, and attended the "Real Colegio de San Carlos". His cousin, Belgrano, would secure him a position in the public administration in the Viceroyalty of the Rio de la Plata.