Manual set up of smtp and imap. How do you do it on iPhone

The answer depends completely on your email service provider. Their help will explain.

If that’s it then go to Settings/General and scroll to the bottom. Just below VPN there may be an entry for either Profiles or Device Management. Tap on it, tap on any profile from the former employer, and delete it. Then restart your phone.

For most email providers it is unnecessary as the device will auto-configure, unless something in the connectivity path is interfering. For example, some Wi-Fi setups or corporate networks have firewalls blocking the transaction that the phone needs to do with the provider to achieve that. I always recommend you do the setup via cellular to avoid that.

Edit (after seeing your pics): yup, iCloud auto configuration. Not negotiable as far as I remember.

According to that article the functions are included in a profile. Which is why I suggested deleting the profile. As that is the only way restrictions can be imposed on an iPhone that must be how it is done.

You cannot set up an iCloud email account manually.

Sorry, I don’t get involved when the need for tin foil hats becomes apparent.