https://goblin-slayer.fandom.com/wiki/Light_Novel_Volume_1 lists that it went continuously from chapters 1 to 15 of the manga which seems straightforward
But then it lists 1-5 and 10-12 of the anime...
LN v 2 similarly 16-30 of manga, 5-10 of anime
Then LN 3 (manga 30-40) has nothing animated (perhaps s2?) while LNv4 (manga "brand new day" ch 1-10) makes it into episode 5 (I assume only partially?) and LNv5 (manga 41-54) is the Goblin's Crown film...
I haven't seen Crown yet, would there be problems in missing whatever parts of LN3/LN4 ?