We are plan to visit Lijiang Jade Dragon Snow Mountain.

1. Don’t worry. It’s safe to take it. Well, you can buy the cable car tickets when you arrive at the scenic area. Besides, you can ask a Chinese friend to help you book the ticket on the internet in advance. I have no idea how long you need to walk if you take a cable car. The big one will arrive at the altitude of 15,000 feet (4,600 meters), while the small one will only reach at the halfway of the mountain.
2. One day is enough for you to visit there.
Referring to the history data, the temperature will range from 45F to 85F in April. It will be cloudy in the most days, and it will be rainy or sunny sometimes.
Hope helpful!

Thank you for reply and details.

How many people can take one rope car?
Is it ok to climb full height?

Generally speaking, it can contain two people in one cable car. Because of the high altitude, some people may have the altitude sickness, but it is okay to climb it with oxygen tanks. Notably, please don’t do the heavy exercise when you feel uncomfortable.