Although advertisement promotes the selling of a good or service, propaganda favors, opposes, or criticizes an individual, concept, movement, or cause in order to accomplish a political or economic goal.
Advertisements and propaganda can indeed be used to successfully advertise different products and services. There are some differences between the two. Advertising is usually done to promote the product or services the best way possible. This means that people are genuinely encouraged to try out and purchase the products when they get the chance. Propaganda also makes use of advertising, and they try to promote the products, but they do not try to encourage the sale of any product.
For example, there may be propaganda of a senator regarding the things that he has done. This will be shown on television just to let people know what things he has already done for his country, but they will not promote that people should vote for him.