MySQL IF Clause in WHERE + Insert Into

Hi I have a dataset where I want to seperate original projects (roots) from copied projects (forked) and insert these two results into a new table.

INSERT INTO root_fork (root_id)
SELECT
    projects.id
FROM
    projects,
    all_projs_limit
WHERE
    projects.id = all_projs_limit.project_id 
    and projects.forked_from is NULL;

and the other is

INSERT INTO root_fork (fork_id)
SELECT
    projects.id
FROM
    projects,
    all_projs_limit
WHERE
    projects.id = all_projs_limit.project_id 
    and projects.forked_from is not NULL;

I want to have both as one SQL statement. Is that possible for example with if and else?