How much should I expect to pay?

Hi there! This past summer was my first time working since turning 18, and I will be filling taxes for the first time this year. I’m pretty uneducated about this whole process (my dad files taxes for everyone in my household), so I hope that this isn’t a stupid question.

Last summer I worked as a summer camp counselor, earning about $3,000. I also did a short PA contract for a local event and earned $320 through that. Neither employer took out anything for taxes. I was told that I should set aside $400 (in total across both jobs) for taxes.

I have this money saved, but I was just wondering how likely it is that I will actually have to pay the full $400??

Sorry if this is a stupid question lol.