There are three main historic cultures you'll want to look into to find this history: The Punic/Carthaginians, Rome, and the Vandals. At different points in time, you probably won't be able to focus on Morocco specifically. The ancient sources for the region just aren't always that detailed or specific, but those three groups should give you a good start.

The are of northwest Africa called the Maghreb in Arabic sources, first enters the historical record as the site Phoenician (Punic) trading colonies around the 6th century BCE. Over the centuries, Carthage (in modern Tunisia) became the most powerful Punic city and ruled over the rest of the region. For the history of Carthage and the other Phoenician cities I can recommend:

• Carthage Must Be Destroyed: The Rise and Fall of an Ancient Civilization by Richard Miles
• In Search of the Phoenicians by Josephine Quinn
• The Punic Mediterranean: Identities and Identification from Phoenician Settlement to Roman Rule edited by Josephine Quinn and Nicholas Vella

Carthage's power in the region was famously destroyed and conquered by the Romans over the course of the three Punic Wars. While Rome outright seized and occupied the territory immediately surrounding Carthage, much of the region became part of Mauretnania and Numidia. Initially friendly with Rome, the Romans eventually fought and conquered both regions. Mauretania is the one to look for specifically if you want to focus in on modern Morocco. I'll defer to the AskHistorians booklist for the thousands of very good books on Rome that can be used to cover this time period, though you'll mostly be interested in single sections or chapters relating to Mauretania, Numidia, or Roman Africa. The one specific book I want to point out is The World of Juba II and Kleopatra Selene: Royal Scholarship on Rome's African Frontier by Duane W. Roller. Juba II was a Numidian prince made into the puppet king of Mauretania by the Romans, who wrote a history of Mauretainia, which is now lost.

In the 5th century, a Germanic tribe known as the Vandals migrated and invaded the region, which I recently covered in this post about Numidia. The Vandals occupied the region for about a century until the Byzantine Eastern Roman Empire reconquered and occupied the region again until the Islamic conquest in the 8th century. For this last time period I recommend: Vandals, Romans, and Berbers by Andrew H. Merills.