A temporary worker who gets fired has the right to stay in Canada until their work permit expires. They have the right to look for another job but they can not start working until they have a new LMO and a new work permit to match.
An immigration application that is based on a job offer, for example skilled worker with job offer or PNP though employer support will most likely be refused if the job offer is no longer there. Immigration classes are do not base on the job offer like CEC for example would continue to run.