Can Kirchhoff's current law only be applied to nodes? Can voltage law only be applied to closed circuits?

Can Kirchhoff's current law only be applied to nodes? Can voltage law only be applied to closed circuits?

If a complex network is regarded as a node, Kirchhoff's current law is still applicable, and the inflow equals outflow. The voltage law does not need a closed loop, and the open circuit also applies, but you have to close the loop, that is, go back to the original position

Kirchhoff's law of voltage and current is applicable to (circuits)
A steady state circuit B transient circuit C steady state circuit and transient circuit

C KCl and KVL are independent of the properties of the components that make up the circuit and can be applied to any circuit

Kirchhoff's second theorem
A simple circuit ABCD has a power supply e, the internal resistance is r, there are three resistors R1, R2, R3 respectively. Choose the direction of detour clockwise, there is only one circuit in this simple circuit, so the current is I
Then there is: RI + r1i + r2i + r3i = E
Why can't e be used to calculate current in parallel circuit

Kirchhoff's second law
Hoff's second law
Kirchhoff's second law, namely Kirchhoff's law of voltage (KVL), is that in any circuit with lumped parameters, at any moment, the algebraic sum of the voltages along each section of the circuit is always zero, that is, when the reference direction of the voltage is the same as the detour direction of the circuit, the voltage takes a positive sign in the formula, otherwise it takes a negative sign. Kirchhoff's law of voltage is the embodiment of the law of conservation of energy in the circuit
Two rules of Kirchhoff's law of current and voltage
The total current flowing into any DC circuit node, also known as branch point, is always equal to the total current flowing out of this node. To explain the above statement, take an example. There are four charged conductors (a, B, C, and D) flowing into the node (black point), and two conductors (E and F) flowing out at the same time. The parallel DC current is added, so that the total current flowing into this node is a + B + C + D, The current flowing out of this node is e + F. these total currents should be equal according to Kirchhoff's first law
Kirchhoff's second law is about voltage. Take an example to illustrate this law. A power supply with voltage a and five passive components with potential differences B, C, D, e, and f form a circuit. Because the five passive components are connected in series, their total potential difference is the sum of the five potential differences, The total voltage on the set of passive components is always equal to the voltage of the power supply and in the opposite direction. Therefore, the sum of the potential differences (including the power supply) of all components in this circuit is always zero