It is possible, in order to complete your profile, to add your company page:

To do this, go to the My Profile tab and then click Edit in the Company field.

Then search for your company in the search bar and if you see your company in the results, click on it.

Your company has been added to your profile!

If you want to modify the information on the company file that you have added to your profile, you can Ask to become Admin:

If your business does not exist when you search for it, you can click Create New Company.

Complete the information requested to create your company profile, then click on ✓ to add your company to your profile.

When you create a company, you are the admin by default.