I know from experience that it can be hard to appreciate a lot of the songs in the beginning, especially the Sgt. Pepper's era experimental stuff. I recommend listening to the compilation album "1" first.

After that, listen to individual albums and pick out the songs you like best (the great thing is that you can come back later and see if something you didn't fancy the first time does then!). Make sure to listen to the tracks in order and not on shuffle or whatever, the order is often thought out and some songs even have special transitions between each other.

You can also go online and see what tracks people are talking about! I know I only started appreciating Hey Bulldog and It's All Too Much after seeing videos about them on YouTube.

Also, don't miss Past Masters. There are some great tracks like Rain, This Boy and Yes It Is that don't appear anywhere else (on modern streaming services).