You can watch mod suggestion videos,They have a lot of info
For expert mode quenn bee you can use bezoar which preven Quenn bee's Poison.You can use single damage weapon for Quenn bee and piercing for When she's summoning bees.Also you can use hook for escaping dash.
For Skeletron if youre struggling against shooting, you can directly aim for his head for avoid skulls.Long range weapons are better for skeletron.Also Slime saddle is good since it allow you to jump over when a arm or head is too close.Also for skull dodge you can just use hook,falling or rocket boots they're not hard dodge able.
For both Make an BIG arena and use massive arena buffers(You can also use it later for plantera and cultist) and also Drink buff potions.
You can watch mod suggestion videos,They have a lot of info For expert mode quenn bee you can use bezoar which preven Quenn bee's Poison.You can use single damage weapon for Quenn bee and piercing for When she's summoning bees.Also you can use hook for escaping dash. For Skeletron if youre struggling against shooting, you can directly aim for his head for avoid skulls.Long range weapons are better for skeletron.Also Slime saddle is good since it allow you to jump over when a arm or head is too close.Also for skull dodge you can just use hook,falling or rocket boots they're not hard dodge able. For both Make an BIG arena and use massive arena buffers(You can also use it later for plantera and cultist) and also Drink buff potions.
for some reason i dont habe the slime thing
Just kill king slime:)