I need your help people

Aaaaaa. I have absolutely no idea what to pack for my trip to Germany!
I’ve got loads and loads of clothes, but I’m so confused.

I’m basically going only for two weeks, and in these two weeks, I’ll be spending around four days in Amsterdam and a few in Austria as well, but I have no clue what to wear.

It’s April, but my dad tells me there’s going to be snow, which means it’s going to be cold. Um, how cold, exactly? Does anyone have any idea?

And how many layers of clothes am I supposed to keep? For some reason, I have a feeling that one shirt and a jacket isn’t going to be enough. Also, is gloves necessary? Hello? Anyone living in Germany (or has been to Germany in April, or has just returned)? I need advice. Like, right now.