I won't advice this for a newbie though it's a very easy way to buy crypto. Most exchanges are not secure and this might lead to data leak which may affect many who ahs their credit cards details stored in the exchange. If one must buy with credit card, I will advice getting a completely different credit card details only for that purpose. You send exactly the lunt of funds you need to make the purchase with the card, use it and leave it empty until next time you want to.