To be able to add system config variables to email templates it is not enough that they are defined in system.xml and added to core_config_data.
You must also make them appear in the list of variables that appear when you click
In the email templates:
To do this you have to define a config path in your di.xml like this:
Reference source: https://magentip.com/change-magento-2-store-logo/
You can upload and overwrite the file in logo file path, for example
If you want to Change magento 2 logo programmatically, go to \app\design\frontend\Magento\luma\Magento_Theme\layout\default.xml
Add this code
If you want to send a completely different email then create one more email template as you did for the customer to admin.
If you want to change Dear to Dear then Pass var to the email template accordingly.
Use try to use call .phtml file in template and then set condition accordingly.
here is my execute function (observer) any other file code add
You can try as below:
$templateVars = array(
'store' => $this->storeManager->getStore(),
'message' => 'We processed your order ID We will contact you soon in mail for the acknowledgement if you not receive mail within 4 hours please get help from ...
First of all you can't add PHP code in html file.
You can add or change email logo from admin.
Please prefer this link Magento DevDocs for Email Templates
Steps to upload logo from admin is :: Magento Admin > CONTENT > Design > Configuration > Select your store scope > > Save Configuration
If this helps you then hit like.