What are the chances for 344 in neet2019 and belongs to AP, SC category

Dear Rajendra you havent mentioned which area you are locale to. AP Medical Seats are categorised into SVU, AU, OU areas and candidates are categorised into locals based on the area they belong to. Neverthelss, in 2018, under State Quota, the cut offs for various areas for  SC Category have been as follows:

AU: 427
SVU: 403
OU: 418

So at 344, it is difficult even to get a Private Medical Seat. Having said that, cut offs change every year and are dependant on various factors like no.of seats available, no.of candidates appearing for the exam, top NEET score and difficulty of the exam. You can also check the cut offs of various different colleges under your Category at:
https://medicine.careers360.com/articles/neet-cutoff-ap