Can someone please clarrify these passages for me ?

Question

"No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal; coin Money; emit Bills of Credit; make any Thing but gold and silver Coin a Tender in Payment of Debts; pass any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or grant any Title of Nobility.”
"No State shall, without the Consent of the Congress, lay any Imposts or Duties on Imports or Exports, except what may be absolutely necessary for executing it's inspection Laws: and the net Produce of all Duties and Imposts, laid by any State on Imports or Exports, shall be for the Use of the Treasury of the United States; and all such Laws shall be subject to the Revision and Controul of the Congress.”
“No State shall, without the Consent of Congress, lay any duty of Tonnage, keep Troops, or Ships of War in time of Peace, enter into any Agreement or Compact with another State, or with a foreign Power, or engage in War, unless actually invaded"

Answer 1

"No state shall enter into any treaty ... (that paragraph) Only the Congress is authorized to do such things. For example, a state, like, say, Maryland, can't coin its own currency, or any of the other things mentioned. States cannot create credit (which is why they have budget crises); the Federal Government can (uniquely the US Constitution allows the creation of fiat credit).

"No state shall...lay any ...Duties..." etc. Again, only the Congress can authorize this from the Federal Government level, or a state can do it with permission from the Congress. For example, Texas cannot collect duties for itself, on goods coming over the border; it can collect duties for the Federal Government.

And similarly with the last paragraph, no state can keep a separate standing army or militia, without consent from the Congress. Everything flows from the pre-eminence of the Federal Government.

As Pres. Lincoln said, a government "of the PEOPLE, by the PEOPLE and for the PEOPLE..."