Final answer:
The biggest problems the British soldiers and settlers faced when moving to Australia in the 1820s were conflicts with the Aboriginal people, the harsh environment, and the lack of resources and infrastructure.
Step-by-step explanation:
The biggest problem that British soldiers and settlers faced when they moved to Australia in the 1820s was the conflict with the native Aboriginal people. As the settlers expanded their settlements and encroached on Aboriginal lands, tensions and violent clashes arose. The settlers took more land from the Aboriginal people, leading to displacement and loss of their traditional way of life.
Another challenge for the British soldiers and settlers was the harsh and unfamiliar environment of Australia. The climate, lack of water, and endemic diseases posed significant difficulties for the newcomers. They had to adapt to the arid conditions, find ways to access water, and face the risk of diseases.
Furthermore, the isolation of Australia from Britain and the lack of resources and infrastructure in the early years also presented challenges. The settlers had to establish sustainable food sources, build their own shelters, and develop trade networks to meet their needs.