How to withdraw an electronic patent application? Can I reapply after I quit?

Yes, as long as the application fee is not paid, it can be withdrawn and resubmitted, so it doesn't matter.

Article 29 Where an applicant applies for a patent for invention or utility model for the first time in a foreign country within 12 months, or applies for a patent for design for the first time in a foreign country within 6 months, and applies for a patent on the same subject in China, he may enjoy the priority according to the agreement signed between that country and China or the international treaties to which both countries are parties, or according to the principle of mutual recognition of priority.