JEE Main

1) NIT, Trichy.
2) NIT, Warangal.
3) NIT, Allahabad.

There is a low chances of getting seat in NIT's as your percentile was not sufficient to get seat in any NIT's, because of heavy competition and demand of seats. So, just give a try. All the best.

No, it is very difficult for you to get admission in LNMIIT. You may try for some other college.

Use JEE Mains College Predictor:
Enter your JEE Main 2019 rank to predict your colleges. https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor.

It is difficult to get a seat in SASTRA as your JEE Main percentile doesn't meet the expected based on the stream, so just give a try based on stream i.e., based on IPE marks.
All the best for your future.

As according to last year records, the cut off for paper 1 for 2019 will be around 95 and for paper 2 will be around 105 marks, but as this time it is totally changes so might this figure might change.

Yes, what you have heard about the placements of Thapar University is true, the college placements as of now is not as worthy as it is in last 4 years, and this is due to lack of good teachers.

With this score, getting this college in the good B.Tech branches may be difficult, as the closing rank in this college is around 45,000 for all the branches, and you might not get into that. But, you can try in the last round of the counselling in that you can get.

Considering your concern only about JEE Mains, I would first recommend you to check that are you well versed with the complete syllabus. Yes, that is absolutely necessary to have all topics (even the smallest and seemingly unimportant ones) completed very well. Now that when you ensure that then comes the real thing. Practice, Practice and Practice. This is the only thing which can help you score well. But, only problem solving won't help you.

With this score, you can expect rank around 15,000 in the JEE Mains or may be less than that. This time, it is totally new concept, so it is hard to guess, but according to last year trends you must have rank around this only.