As a Student

When using AssignmentOS with Moodle, you don't need to explicitly send an assignment to a student. Instead, any student enrolled in a Moodle course containing an AssignmentOS assignment can access it directly from their Moodle account:

Student assignment in Moodle

The student can then take the assignment directly inside their Moodle account. See here for more details on the student workflow for an AssignmentOS assignment.