@jamilhaddadin 

Just using the Play1s there is no way to get the external audio of the projector into Sonos system. If the projector supports BT audio, a BT compatible Sonos Speaker like a Roam (SL), Move2 or Era would be an option to get audio to Sonos. Then you would be able to group the Play1s to the BT receiving Sonos Speaker. 

Thank you I will follow your advice

is Two questions
1- Can i use Sonos move 1 instead of 2
2- I have 4 speakers (Pay 1) can i connect the 4 of them? or should i be able to group only 2 + the move 1? I would appreciate more help here

Move 1 won’t work, because it can’t use BT and wifi at the same time. It was the first Sonos BT device and has got older hardware. 
You can group as many rooms as you like.

Even you can mute the BT devices room itself, if you just want to use it as a „BT line in“. 

Wooow that last idea is super super smart :-) 

Thank you I will follow the instructions now

@jamilhaddadin 

So a Sonos Roam SL would be the cheapest option to realize that.