Changing visa status

Hi,

I have a question, if I get a full time technical engineering job offer in a good company through an agency like Adecco or other agencies so can I use that contract to change my visa status with Ausländerbehörde? Assuming I am at the end of my student visa or on a job seeker visa and with that job contract can switch to a valid job visa? Are the contracts from the agencies valid??

If anyone has experience in this situation or knows about it please share..