if I set up i-cloud mail on my Mac air will it automatically change my Apple ID from a gmail address?

No, your Apple ID will not be changed. You can use both email addresses. Synced? Not unless you forward all of your mail from one address to another.

If you ask Apple to create and associate your Apple ID with an iCloud email address with your Apple ID, you will gain an iCloud email address.

You will not lose the Gmail email and address, but you will need to add it as a second email account.

Change your Apple ID - Apple Support

Your primary Apple ID is say example1@gmail.com that is signed from Mac system preferences its permanent , if you create a new Apple ID from web account How to create a new Apple ID - Apple Support

See the section - Create your Apple ID on the web

The primary Apple ID credentials will be required , the new Apple ID is say example2@icloud.com

It can be added in Mac system preferences > internet accounts to sync only from your Mac , the other devices will only sync with your primary Apple ID account when they are also signed in with same Apple ID and password on the same network .

You mentioned - still use I-cloud email address?

When it's added in internet accounts it can be used .

Use your Internet accounts on Mac - Apple SupportUse your Internet accounts on Mac – Apple Support (AU)

Change Internet Accounts preferences on Mac - Apple Supportsupport.apple.com › en-in › guide › mac-help › mac

Add an internet account - Apple Supportsupport.apple.com › guide › mac-help › mac

Note : as you mentioned , I want to keep that gmail address as my primary email can I do this and still use I-cloud email address? Also can they be synced?

Answer is yes , your additional secondary mail address say example2@icloud.com it will be configured from Mac , you can get mails from your recipients when you reveal only iCloud mail address say example2@icloud.com to them .

tygb wrote:

Your primary Apple ID is say example1@gmail.com that is signed from Mac system preferences its permanent , if you create a new Apple ID from web account How to create a new Apple ID - Apple Support

Do not create a second Apple ID here, as that will block access to your preferred Apple ID for some months.

If you want an Apple ID to migrate from gmail hosting to newly-created iCloud hosting at Apple, reconfigure that in the existing Apple ID, then add the gmail as a second mail account once the Apple ID is migrated to iCloud.

See the section - Create your Apple ID on the web

The primary Apple ID credentials will be required , the new Apple ID is say example2@icloud.com

It can be added in Mac system preferences > internet accounts to sync only from your Mac , the other devices will only sync with your primary Apple ID account when they are also signed in with same Apple ID and password on the same network .

You mentioned - still use I-cloud email address?

When it's added in internet accounts it can be used .

Use your Internet accounts on Mac - Apple SupportUse your Internet accounts on Mac – Apple Support (AU)

Change Internet Accounts preferences on Mac - Apple Supportsupport.apple.com › en-in › guide › mac-help › mac

Add an internet account - Apple Supportsupport.apple.com › guide › mac-help › mac

Note : as you mentioned , I want to keep that gmail address as my primary email can I do this and still use I-cloud email address? Also can they be synced?

Answer is yes , your additional secondary mail address say example2@icloud.com it will be configured from Mac , you can get mails from your recipients when you reveal only iCloud mail address say example2@icloud.com to them .

Configuring an alias address for an iCloud email address is a different matter.

PS: I'd also encourage the OP to set up trusted devices and trusted telephone numbers, and account recovery contact details before migrating from the existing gmail provider to Apple and iCloud as the email provider, so that access to the Apple ID is not lost if something goes odd.

The author said - I want to set up I-cloud mail on my new Mac air M2 but my Apple ID is my gmail account.

They are setting up a new Mac , in initial stages third party mail services like gmail , yahoo mail address is required to sign in with as an Apple ID , the mail address say example2@icloud.com can't be created directly from Mac .

However when Apple ID say example1@gmail.com is signed in Mac , further they can create new Apple ID say example2@icloud.com from web , alias of iCloud address is created when Apple ID say example2@icloud.com is signed in Mac system preferences , account recovery is done for 2FA accounts when the password and account credentials are lost .

In new Mac secondary authentication account is created initially in which three answers for respective questions , date of birth , rescue mail address and its password are added , further its a choice to add trusted numbers and verify them and convert the account into 2FA .

The author also said - will getting an i-cloud email address change my Apple ID?

No , once Apple ID say example1@gmail.com is signed in Mac , it will remain signed in , the second Apple ID say exammple2@icloud.com can be created from Mac , but this will be a simple mail address unless its switched and signed in Mac , simultaneously credentials for primary Apple ID ( say example1@gmail.com ) are used to create it .

Lastly they wrote -

also my gmail account is connected to all my professional communications and web urls like web ex Microsoft etc., I want to keep that gmail address as my primary email can I do this and still use I-cloud email address?

They want Microsoft , that is again to be downloaded in new Mac , the new iCloud mail address say example2 @iCloud.com can be added in Mac system presences > internet accounts .