What is the difference between en Reklame and En Annonse ?Feel free to just provide example sentences.

If it's clearly an advertisement, it's en reklame; If it's announcing something else, especially if it's a casual one-seller-one-buyer-style thing, it's typically billed as en annonse.

Columns of people (especially individual people) selling their stuff or services and X seeking Y sections are annonser, as are general proclamations with do not promote something specific.

They are often used interchangeably.

Perhaps the easier way to draw a sistinction is by looking at their etymologies. Å reklamere is to advertise, i.e. to promote something. Å annonsere is to announce, i.e. to spread a message; annonsere does therefore not necessarily encourage specific behaviours or opinions, and is more about informing than about suggesting a course of action.