Toilets, Sinks, Showers, Tubs and Disposals - Stand up shower drain

HELP!!! I have removed my old stand up shower. Now I have problems. They are as follwed: (1) The 1 1/2 drain pipe comes up at an angle. If I install as is,the the base of of the shower will need moved 2-3 inches from the back wall. The pipe is maybe 3 inches long before it goes in to another conectin point ( maybe a tee for the vent pipe) the pipe which comes out of the tee(?) comes up to a 90 then runs under the floor. Not sure where it goes from there

(2) What size should the drain assembley be to match an 1 1/2 inch pipe. They gave me a 2 inch drain assembley for the base of the shower. Does the drain pipe just go up and in the drain assembley? The directions do not give any specifications for the drain pipe. The drain assebmley did not come with any specifications either. It just tells you how to assemble all of the gaskets and rings. Please help...I am trying to avoid the cost of a plumber

Shower drains should be 2". If the existing drain is not in the right place or size, it needs to be moved and/or modified. You question suggestes that it migh be better if you consulted a plumber. Assuming the drain is not buried in concrete it is usually not a major job to change.