Is it easy to get admission in Symbiosis for Btech?

Well, it won’t be as easy as cutting butter with a knife.
But it’s not that difficult either.
Academic wise the entrance test is relatively easier than other tests like MH-CET, UPSEE or VITEEE.
But competition is high. In addition to that if you want CS-IT, then the competition doubles and your chances become half of what they already were.
Also, the admission pattern is not constant. When I took admission in 2012, the competition was tough even for civil (which usually fills out late) and even though I had scored just 22.2% in AIEEE (There was no JEE mains at that time) I was just able to bag the 6th last seat in civil engineering department. At this moment I had a choice between civil, mechanical and EnTC. CS-IT were filled.
2013 batch witnessed ease during admissions. 2014,15 batches say they faced competition. So there are chances that you too might face a bit of competition.
Having said all that, I would suggest you to be confident and positive. If you get a seat here at SIT, enjoy those 4 wonderful years!