Soup or stew is about the only traditional way to prepare lentils pretty much everywhere, traditionally eaten with bread. The lentil+wheat/rye combo is to Indo-European cooking what beans+maize is to American cooking, and rice+beans to Asia. Africa is also lentil territory the grain situation there is... complex.

In any case yes it's going to be soup or stew in whatever viscosity and degree of mushiness you want but you'll find a metric fuckton of different recipes.

If you want something ready-made there's lentil crisps which actually are very good but also quite a bit more expensive than the usual potato or maize fare.