Reading ms on Lock Screen

Hello guys. I have a problem an hope I can get help.

im living in japan an we use LINE here a lot. Sometimes I get messages from people that I don’t want to talk to. However , sometimes the message be long an I can’t read it all on Lock Screen. If I swip left an view it. Will the person know I read the message? It’s the only way we can read long messages without going on the app directly. But I don’t want them to know I read it. Help please 🥺.