If you are talking about CPNET 2019, the start date for online application will start in the First week of June. The online applications will close by First week of July. From the 3rd week of July, you will be able to download your admit card. The entrance exam will be in the last week of July and the answer key will be published around the same time. The results will be declared in the last week of July and the merit list will be published in the first week of August. However please remember that these are all tentative dates and the actual dates are yet to be announced. 

Hello

Admission procedure vary from college to college. Application forms for admission to B.Sc Nursing in King George's Medical University are available generally in the month of May and entrance exam is held in July.
If you want to know about any other college do let me know so I can answer accordingly.

Good Luck!