Modem & shared Router use = No wi fi from modem

> Using a modem in main house. Running cable to router in garage [...]

   If your target audience consists solely of people who can see these
devices (maker, model number, connections, configurations, ...), then
you should just write your question on a piece of paper, and stick it on
your wall.  Save yourself all this computer-forum bother.

   For the non-psychics here, some actual information might be useful.

> Any tips ??

   Try to imagine that you had to read this stuff, and make some sense
out of it?  Also, as usual, showing actual actions (commands) with their
actual results (error messages, LED indicators, ...) can be more helpful
than vague descriptions or interpretations.