All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad
is His slave and Messenger.
You are permitted to work on a lawful product or project, whether by promoting or selling it, as long as your promotion does not include any prohibited elements. The established view among scholars regarding the ruling on advertising and earning from it is that it is permissible in principle if the product or service is lawful and the advertisement avoids any Islamic violations, such as immodest images, inappropriate music, or similar content. If such violations are present, the advertisement becomes impermissible.
Allah knows best.