Looking For Best Way to Buy Cryptocurrency For Cash

Investigating best way to buy crypto coin for cash using my debit card. I've investigated Changelly, 247, and looked at other ways but it's a little daunting. The exhange rates seem to be enormous. Looks like I have to give up over 50% for a fee to buy coin and that is ridiculous.
Would appreciate any input on a better way or the best way to buy cryptos with cash. Need to get in the market soon before it really goes boom. I understand the US Congress will pass legislation by the end of September that will allow cryptocurrencies as legal tender. So, it's time to get on the bandwagon before it's too late.
Please help all you knowledgeable ones.