Right now you've encoded it such that a user can have multiple companies, so the relation user:company is 1:N. I'd suggest you make that relation N:M so a user can have multiple companies, and a company can have multiple users, as that's more realistic.
To do this you need an extra table with the PK of users and the PK of job_offers as its PK.
If you don't want to do that: yes, your scheme is incorrect. The fact that users_id_user is a PK in the company table is in the PK doesn't make any sense, and that your PK in the job_offers table makes even less sense (did you notice that a company can have no more than 1 offer the way you've set it up!?).
I'd say that users_id_user in the company table should be in the primary key, but in the foreign key, and then put company_id_company in as an FK in the job_offers table and create and id_job_offer as the PK in that table.
PS. Please make up your mind about using singular or plural. Right now you have a table "users" (plural) with a field "id_user" (singular), a table "company" (singular), and "job_offers" (plural).
If you keep mixing it like this it come will come back to bite you in the behind one day.