[skyhawkone]

Do u need a pea drain? The shower will link into the new tiolet drain. Also two sinks will feed into the shower drain. I will install an air vent with the new air vent system that doesn't require you to go througj the roof I also have to brezk the floor

[ma0641]

I will assume you mean a P Trap. All fixtures except a toilet must have a trap. Need to excavate under the shower to get clearance for trap or elevate shower. I will also assume you are doing this without a permit or they would have told you so. Double vanity can use 1 P Trap if properly installed. Do you know where to vent? Size of drain pipes? Proper fitting to use?

[speedball1]

Do u need a pea drain?

As already stated, If drains it MUST be trapped.

The shower will link into the new tiolet drain.Also two sinks will feed into the shower drain

That's called wet venting the shower.
Check your Building Department to see if AAVs ( air Admittance Valves) are allowed. Good luck, Tom

[skyhawkone]

One sink is in the washroom and on the otherside of the wall is a kitchen sink. The vode does alliw me a venting

[speedball1]

One sink is in the washroom

If by "washroom" you mean the bathroom you will install the drainage as shown and vent the lavatory with a AAV. Also the kitchen sink will require one as well. Good luck, Tom