You'd be momst welcome to attend, the last elections were a few months ago so, I'll keep you in mind but it will be a couple of years before you will see countrywide elections in China again.
You'd be most welcome to attend Beijing any time during the Two Sessions which are held every year, but again, you've just missed them, they were in March. There you could meet with any of the thousands of elected delegates and representatives who have been elected to serve and represent them by their communities or workplaces.
Alternatively, if you're more interested in how the party works than the government, then I suggest to attent the National Party Congress, which is held every 5 years, but again, you missed the last one in October and the next meeting is in October 2027.