Complex sentence: With an open position in the regiment of the Dragons, Dupaix decided to transfer himself to New Spain where he arrived in Veracruz on February 4th 1791, where he was in awe of all the flowers and vegetation.
Split into simpler sentences: With an open position in the regiment of the Dragoons, Dupaix decided to transfer to New Spain. He arrived in Veracruz on February 4th 1791 and was apparently in awe of all the flowers and vegetation.