Is what my father says true, that Islam has deeper stages than Sharia, such as "Tariqa (the spiritual path), Haqiqa (the ultimate reality), and Ma'rifa (gnosis)"?

Extremist Sufis claim that beyond the Sharia there is a reality, a path, and a gnosis (معرفة) acquired through unveilings (مكاشفات) and influxes (واردات) upon the heart. This results in great misguidance, manifested in: 1. Their belief that the texts of the Sharia alone are insufficient to reach a high rank in true knowledge of God. This attributes deficiency and imperfection to the Sharia, even though the religion has been perfected. 2. Their considering unveilings, inspirations, and spiritual experiences (أذواق) as a path to knowledge, whereas these are neither proofs nor reliable, but rather a product of the path one treads.

The only way to draw near to Allah is to follow the Sharia of the Prophet, peace and blessings be upon him.