So step one get your free custom domain via Freenom - then signup to ImprovMX!
Set your entries over at Freenom
See Setting an MX record at Freenom
You’ll likely see “Waiting for DNS” for a small time until DNS finally updates.
Boom!
Free active email forwarding which is reliable and fast!
Now you can instantly manage your free email forwarders, ensure the catchall at the top * is setup to a valid email which can receive all the emails that aren’t setup.
You can also setup tons of personalised inboxes for your friends / family and yourself!
Using this option allows you to keep your DNS set to default > Freenom
This allows you to freely manage your DNS at Freenom while keeping URL / Domain Forwarding active and pushing visitors to your 000webhostapp hosted website via your custom URL!