Can I go to the domestic website when I immigrate to the United States?

Baidu can. In fact, many foreign users can't open it because the network is not good. Of course, some IP in China is blocked by firewall.

Generally, applications like Baidu Post Bar can't be downloaded abroad, but the web version can be accessed. You can download the Chinese version at home and install it abroad.

Youku video website seems to be inaccessible abroad and has restrictions.