I'm planning to buy NIKON 5300?

I'm planning to buy my first DSLR camera between 30 -40K. I came across CANON & NIKON. I prefer to buy NIKON 5300. As i'm beginner / enthusiast guy can you suggest is this good choice or help me by your chice.

Don't be fooled by the term "entry-level". It refers to budget not skill. Since there's no such thing as a dSLR for beginners, I strongly advise you to buy at least a mid-level model to enjoy using the camera outright. This will save you money in the long run since most beginners who bought cheap eventually had to buy a better camera when they already learned.

With Nikon, a good starting point is the D7x00 series while with Canon, choose from any of the 2-digit models. Pentax on the other hand is confusing since their low-end models have some high-end features giving you more bang for your buck.

Mirrorless cameras are the future.

The Pentax K-50 is a better camera on paper than either of the two you mention, and made by the oldest SLR manufacturer in Japan - only intelligent people have heard of it, though.