About Bloom Into You: Regarding Saeki Sayaka
I've watched the anime but I'm not a big fan of manga, can I go straight to that novel with just the story portrayed by the anime?
The first volume is about things happening to Sayaka before the manga storyline, so sure, the anime should be enough.
The second volume is supposed to be on the same timeline as the manga however (and the third one is about after) so perhaps that won't be the case here. These haven't been released yet though.