My house is a 5yr old,I want to install a 3 piece bathroom and a sink in basement,I want DIY,I attach PIC below,my question is 1,can I tap the sink drain into the main drain stack directly up the floor.2,where is location of main sewer pipe in the house,I heard it is about 4' from the wall.is this right? And how deepth is main sewer pipe usually?3,I can see the vent for main drain stack,so if I break out the cement floor,how to connect the pipe .

Layout

1or2 is right way? Or both?

"1or2 is right way? or both?"

Sorry my friend but the answer is neither one of the plans would pass.
# 1 has the toilet discharging directly into a unvented shower as does #2 which should be a shocker to anyone taking a shower when the potty's flushed.
The plans designates no vents that are shown. If you keep the present configuration then the toilet will have to connect downstream from the shower, the lavatory will have to be vented and the shower drain line will have to have a fitting rolled up on a 45 degree angle and a vent taken off that. I'm still trying to figure out what you're doing with the kitchen sink in #1. Back to the drawing board I'm afraid. Cheers, Tom