As per your details, your ascendant is Gemini, Lagna lord Mercury is with Sun, Guru in third house Leo.
Sun is the Lordship of 3rd house and Sun is in own house Leo with 7th & 10th lord Guru, Lagna lord Mercury.
So native is a genius. He has in-depth knowledge of all subjects and has a high-level academic career. As a result, he will be the best in the class.
Native has a good view of Administration, Politics, Law & Business.
During Mercury dhasa native will have a successful career. His efforts are going to succeed. He will get name, fame & wealth during this dhasa. The native will start a new business. He can get support from the government side and bank & judicial sector.
For strengthening Mercury native should pray to Lord Maha Vishnu every day. Chanting Vishnu Shasara nam & Narayan Gayatri is the best way to get his blessings. Reading Bhagavad Gita is also an excellent way to get the blessing of Lord Maha Vishnu.