Should I apply vaseline (for eczema) everyday?

You can use it every day but you cannot cure eczema with it. You need to get medication from your doctor in order to cure it.

"You can use petroleum jelly on eczema-prone areas, to help combat the dry skin symptoms. Your doctor may also recommend it be used in conjunction with specific eczema treatments. If you're using Vaseline® Jelly for eczema, it's important to know that it won't heal the skin condition."