Child tax credit, EIC and dependent care?

1. Can you explain how the new Tax code impacts EIC ? What is IEC and how does it apply to a moderate income (70k) as opposed to someone who makes $130k  a year?
 
I was told EIC is earned income credit.  It is generally for people making middle to lower incomes and is a huge tax benefit and it benefits a qualified parent who is in the middle to low income bracket. Is this an exemption or is it something else? Does this apply to people who make above $130k a year? Who does it make more of a credit for? Who should it be applied to?

2. Can the custodial parent who qualifies claim the dependent or child care tax credit as an exemption? Or some sort of benefit? What are the criteria to be able to make this claim? I generally pay over $6000 a year in child care while I work. Her father pays for no childcare. Does this not apply to someone who makes over X$ a year?
 
Does it have to be the custodial parent or can it be either the custodial or non custodial (basing that off of the parent who has the child at least half the nights or is the residential parent as defined in IRS law) or is that it-relevant? As I understand it’s an exemption where you reduce your taxable income by the amount of dependent care paid for to a provider while the parent is working. If it’s not an exemption can you explain how it is applied to a parent who pays this? 

3. The child tax credit - my understanding is this applies to the residential or custodial parent who has the child for more than half the year?  Is this a flat credit or the same for anyone who makes less than $200k? 
 
What are the child related exemptions or deductions that changed or went away with the new 2018 tax code?
 
Thank you for your help. If you can help me clarify and use the correct terms  with the relevant federal or its law that would be appreciated. My family law attorney is confused about the new tax code.