I'm looking for a job in Qatar. If I get a job can...

We would like to inform you that regarding the cancellation of the visa, who has the right to cancel it is the previous sponsor or his representative, and the worker can't cancel it himself, but in the case of proven abusive and intransigent employer sponsor to cancel without any legal justification so the Labor Office can usually revoke the visa, which only authorizes the sponsor or his delegate on his behalf (e.g., the representative in the case of companies) to proceed with the cancellation of the residence visas he guarantees.
** However, according to the law, imposing the ban on the company is one of the reasons for canceling the visa and this is through the Ministry of Labor and Social Affairs as indicated by the law
Article 21
The employer, the Competent Authorities, and the Ministry of Labor and Social Affairs may agree to transfer the Foreign National laborer to another employer before the time limit in the contract has been reached or after five years of working for the employer if the contract did not specify a time period.
The Foreign National laborer may, with authorization from the Competent Authorities and the Ministry of Labor and Social Affairs, transfer to another employer in the event of the Recruiter’s death or dissolution of the body corporate for any reason.
In all cases, the employer serving as the Recruiter shall not have his legal rights, or the contract between him and Foreign National, violated, in accordance with the referenced Labor Law.
The aforementioned article organized the cases of which the employee can transfer to another company as follow:
• With an approval from the employer (Whatever the contract type is)
• After completing five years on unfixed term contract
• The end of the fixed term contract
• The death of the employer
Thus, returning to what was mentioned in the question, you can transfer due to the employer agreeing to that, and you must submit an application in this regard to the professional bodies, accompanied by what indicates the approval of the employer or personally going for approval, and in the event of resigning, it may result ban to entry to the country again for a year