What are the Karma yoga, Bhakti yoga, Raja yoga, and Jnana yoga as per Gita?

These are the only four realities in your life: body, mind, emotion, and energy. Whatever you wish to do with yourself, it must be on these four levels. Whatever you wish to do, you can only do it with your body, your mind, your emotions or your energy. If you use your emotions and try to reach the ultimate, we call this bhakti yoga. That means the path of devotion. If you use your intelligence and try to reach the ultimate, we call this gnana yoga. That means the path of intelligence. If you use your body, or physical action to reach the ultimate, we call this karma yoga. That means the path of action. If you transform your energies and try to reach the ultimate, we call this kriya yoga. That means internal action.

The stages of Bhakti yoga broadly categorized into 9 levels, They are:

1) Shraddha: Beginning stage of bhakti yoga, which involves having faith and trust in the existence of a higher power or divine form (Paramatman/ Brahman)

2) Sadhu-sanga: Associating with like-minded people who share similar spiritual interests and goals, as well as seeking guidance from spiritual teachers or gurus.

3) Bhajana-kriya: Engaging in devotional practices such as chanting, singing, and praying to one's chosen deity or divine form.

4) Anartha-nivritti: Purifying the mind and heart by eliminating negative tendencies and attachments, which can hinder spiritual progress. 

5) Nishtha: This stage involves developing a steady and unwavering devotion towards one's chosen deity or divine form, which is not swayed by external circumstances.

6) Ruchi: Experiencing a deep sense of joy and satisfaction in one's devotional practices, as well as a strong attraction towards the divine.

7) Asakti: Developing a strong attachment and love towards one's chosen deity or divine form, which surpasses all other desires and attachments.

8) Bhava: Experiencing intense emotional states such as love, longing, and ecstasy in one's devotional practices, as well as a deep sense of connection with the divine.

9) Prema: This is the final stage of bhakti yoga, which involves experiencing unconditional love and devotion towards the divine, and achieving complete union with the chosen deity or divine form.