So I just started the course with Jonathan Estabrooks, and it's been fun so far! I'm only a few days in and have been learning the warm ups like lip trills and such. How important is it that I'm singing the same exact notes I'm playing on the piano? it takes me awhile to find the right note, so I tend to spend the majority of my time trying to match the same note on the piano which isn't too bad when I'm doing the oo's and ahh's but the lip trills are a bit hard to hear. So in short, should I be trying to match the note or just get the general intervals going?

Great question! If you're singing along with the video, it's ideal to match pitch with the teacher/piano (in a different octave if needed, depending on your comfortable range). 

If you're doing the exercise on your own, you can take the pattern/intervals and sing within your comfortable range, matching pitch with your own piano instead. 

I hope that helps, and please see below for 2 lesson series on singing in tune:

https://www.30daysinger.com/tutorial/how-to-sing-in-tune-for-beginners-part-1/1

https://www.30daysinger.com/tutorial/how-to-sing-in-tune-for-beginners-part-2/1