Hi, I don't think this can be done as you describe, I am pretty sure that the modem router must be wire/connected to at least one pc.
But to be sure, I would advise you to put this Post into the Networking section of this Forum.
Surface Pro 5 News - release date, UK price, features, specs
Gear VR vs. Daydream: Which delivers the best VR experience?
Best Mac antivirus 2017
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.