The invention patent has been declared in China. Can I apply for foreign patents again?

Of course.

As long as it is not public, it is ok.

If you claim priority, it doesn't matter if you apply for a foreign patent within 12 months.

Publicity is a legal procedure, which does not require the consent of the applicant. Except for confidential patent applications, everything else must be made public. Confidentiality is to be audited, and confidentiality is really necessary.