I don't think if you skipped films you'll go into Doomsday confused.

Look at the opening of Infinity War. Thor and Hulk are in space. When Bruce returns to Earth everyone is surprised to see him. Bruce is surprised to learn that Tony and Cap are fighting.

In theory you could say that you have to have seen Thor Ragnarok to understand why Thor and Hulk are in space. You have to have seen Age of Ultron to understand why Hulk was missing. You have to have seen Captain America Civil War to understand why Tony and Cap are on bad terms.

But when you watch the film you're not confused.

Let's say you skipped the Doctor Strange films, he gets a whole introduction when they explain the Infinity Stones, plus a fight sequence to see more. If you skipped Age of Ultron you don't know who Wanda and Vision are, but they get a whole character moment intro and then again a fight scene to show off who they are.

Obviously if Doomsday is a bad film, then yeah it will be confusing, that's what will make it a bad film. But if it's a good film you can just have a passing knowledge of the MCU, the last film you could have seen could be Endgame, and it'll still work.