Is this your first time reading? This is perfectly normal. Different people will have different levels of grammar understanding and possibly reading practice from other sources like textbooks or graded readers, while others might be operating on a handful of basic grammar tutorials and whatever vocab they’ve picked up in Wanikani. An important thing is the thing that makes reading easiest is… more reading.
Also the first book club section here is quite useful advice
(And similarly, the advice I got from @TobiasW on my first book club: ルリドラゴン ・ Ruri Dragon 🐲 Week 1 - #2 by TobiasW )