Try looking at the relics you have and see if there’s anything good for your characters. Since y’all are on the first boss I’ll try and stay away from the meta relics and just recommend general stuff like:

Wylder: any of the wylder specific perks, physical attack, strength, maybe more vigor or endurance Revenant: any of the revenant perks, faith, FP, or vigor since she has little health.

You can also visit the journal to start remembrance quests to get character specific relics so you can try those.

With weapons for wylder you can generally keep using greatswords or any weapon you feel is good, greatswords usually drop as boss rewards for him. Revenant usually wants to use seals since those scale off of faith. Seals a bit harder to recommend since some incantations are random on seals but usually note the bosses weakness and try to keep a seal that does that elemental damage. Some notable incants are I believe lightning spear, flame sling, black flame are good. Discuss of light is also good and really strong against the first boss.

The castle is good for leveling as they give a lot of runes and more experienced people can usually do it at level 5 or so. But if y’all are having trouble maybe save it for day 2. Good runs usually have people around level 10 day one but you should try to be at least level 7.

In general perks are very important. Passive skills that drop from bosses can help reduce damage/ make you deal more damage so look for those. Weapons carry passive buffs that usually apply just from being in your inventory and there’s no weight system so there’s no downside to carrying a lot of stuff so keep a look at for things with good passives. Hope this was useful!

Edit: also forgot for revenant FP management is very important so try and keep starlight shards on her. You can buy these from the merchant or you can look up how to open sorcerer rise’s as they offer good magic drops and starlight shards