Try beating the Queen bee before fighting Skeletron
Skeletron isn't supposed to be one of the first bosses you face. Also, if you just got the game, playing on expert mode is just asking for pain and suffering.
Do you want tips or mercenary?
Expert mode was meant for players who already know a lot of the game and still want a challenge to keep that knowledge spiced up. If you choose Expert Mode on your first run, and you don't even know what to do. Then you'll be progressing really slowly. With lots of frustration.
I've done beat Cthulu and Slime King and I chose expert mode from the start cause I like a challenge
Get a nurse house there. Also, the slimy saddle allows you to jump onto his head when he spins and safely get away. Just don't ride him too far up!
thanks for the info @TheWorfer27
Maybe you could go underground to find chest items so that you can increase your chances of beating the other bosses?
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