Session id when linking tables

Hello guys!

Im been having some troubles understanding this, i have a table called Company, and one named Client. The idea is i create a company, and then, i can create clients related to it.

i want to do this using sessions, but i still dont get laravel sessions(one month on laravel =D)

my table company has an id and the client table has one foreign key related to that one.

how could i do this?