Not if you want the new turf to root and grow properly, no. You can bury the existing turf upside down under 3 inches of soil, then lay new turf on top of that though, but you may find you end up with an uneven lawn over time, so burying it deeper would be best.

I don't advise doing that. As the old turf decomposes underneath the new turf it will create empty pockets which will collapse and give you a lumpy, bumpy, crumpy looking lawn -a moonscape.

What you are going for is a huge job. You'll need to build a retaining wall around the area you which to raise. Then truck in a few tons of topsoil.

More important, you will have to depend upon a landscaper who has much more knowledge than you have with regards to such an undertaking. Why not try lifting a 6x6ft section of your lawn first and see how you feel after you have done it.....thinking about doing things never makes one sweat.

Also remember that changing the grade around any trees in the lawn will most likely kill them over the next 1-5 years.