How to buy ethereum with bank transfer? (with the least fees possible!)

Hey,

I'm a minor, it's hard for me to get into crypto, because you're not allowed to have a credit card when you're under 18.

I can only do small amounts through the visa of my mom and that sucks.

I have a debit card with bancontact (I live in Belgium), it is so hard to find not shady places to buy crypto with a debit card, and I've searched for places to pay with bank transfer but the fees are INSANELY high.

I would like to buy Ethereum directly into my metamask with the least fees possible.

I hope someone can help me out.