Hi I want to create multiple task instances with different credentials to get data from several accounts

with Flow("import") as flow:
    for i in range(5):
        res = import_task(
            command="echo $CREDENTIALS",
            env={
                "CREDENTIALS": str(i)
            },
        )

But in that case all tasks will run in parallel, which will cause the request limits to be exceeded Can I run those tasks sequentially ?

Yes - by default your flow uses LocalExecutor and everything runs sequentially You shouldn't use a for loop in a Prefect 1.0 flow - you would need mapping for this in Prefect 2.0, you can run for loops and arbitrary Python code though