The MTR station Tsim Sha Tsui is very close to your hotel. So, most of the trip could depend on HK MTR.
To Ocean Park: please take the MTR from Tsim Sha Tsui to the next Admiralty. Out of the Exit B, you could find the bus 629 which could take you to the park directly.

To Disneyland: also take the MTR at Tsim Sha Tsui and then get off at Lai King. Then, please take the Tung Chung Line and transfer to Disneyland Resort Line at Sunny Bay. The terminal is the Disneyland.

To Big Buddha: you could arrange visiting it and the disneyland together since they are close to each other. Anyway, a route starting from the hotel. Take the MTR at Tsim Sha Tsui and then get off at Lai King. Then, please take the Tung Chung Line to its terminal of Tung Chung. Then, you could find the cable car of Ngong Ping 360 which lead you to the Buddha directly.