My story seems very linear, how can I make my campaign more complex?

First, sorry in advance for formatting I’m on mobile currently.

As the title says, Many of my plot points and story beats seem to be very linear and I want to know the best ways to”spice things up”.

I currently DM a group of 5 players, A human Druid, a dwarf paladin, half-orc warlock, elf ranger, and elf monk. Currently they’re all level 2 and loving the campaign so far but they’re all relatively new to dnd, but have played before in a one shot of mine previously.

Is there a way to make my world feel more alive? I’ve written lore regarding the various races of my world but feel it kinda slows the game down reading three pages of text.

Any help is welcome!