Answer
In my answer to your previous question, I clarified how the two are different. Please take the trouble to read it once.
In brief, Bhagavat Dharma is a Vaishnava religious stream that is based on the Bhagavata Purana, whose presiding deity is Sri Krishna (and also Sri Vishnu), and whose primary mode of practice is devotion (bhakti).
Bhagavad Dharma is that stream of Sanatana Dharma in which the Bhagavad Gita is the principal scripture, and the Sri Ramcharitmanas and the Bhagavata Purana are two supplementary texts — accepted only to the extent that they do not contradict the words or the spirit of the Bhagavad Gita.
For example, Bhagavat Dharma, although it does not strictly enforce the caste system, tends to lean towards a birth-based varna system.
The Bhagavad Gita, and the Bhagavad Dharma based upon it, does not believe in the caste system; rather, it upholds a varna system that is based on guna (qualities), karma (actions), and svabhava (innate nature). However, even this system has now largely broken down because the world has changed and people frequently change their profession or occupation. Therefore, determining varna on the basis of occupation has become difficult.
In Bhagavad Dharma, Sri Hari alone is the ultimate object of worship, and since Sri Krishna and Sri Rama are both manifestations of that same Supreme Being, worship of both Sri Krishna and Sri Rama is practised. A follower of Bhagavad Dharma may choose any one of these three — Sri Hari, Sri Krishna, or Sri Rama — as their Ishta Devata (chosen deity) and take refuge in that form. However, bhakti (devotion) alone is not sufficient for their worship; alongside devotion, the practice of Jnana Yoga (the path of knowledge) and Karma Yoga (the path of action) is also essential. That is to say, the path of practice in Bhagavad Dharma is 'Samanvaya Yoga' — the synthesis of knowledge, action, and devotion.