I plan to ride a mountain bike from Foshan and Guangzhou to Chengdu. What should I pay attention to?

Route, direct Baidu map. Dedicated navigation should not be needed, not to mention the troublesome operation, and power supply is also a problem. It would be nice to have mobile navigation. Tents and stuff should be forgotten. After all, it's hot after riding so far every day. It may be more cost-effective to take a bath and have a good rest every night.