Hint : Try to find equivalent resistance of the circuit and then find current using Ohm's Law.
Step 1: Find equivalent resistance of the circuit.
Given: Two resistors of 8Ω in parallel. One resistance of 4Ω in series with above combination.
Net resistance of two resistors of 8Ω
1Rnet= 1R1+1R2
1Rnet= 18+18
⟹ Rnet=4Ω
Equivalent resistance of whole circuit
Req=R4Ω+Rnet
⟹ Req=4Ω+4Ω=8Ω
Step 2 : Find current flowing in the circuit using Ohm's Law.
Ohm's Law V=IReq
I=8V8Ω=1 A.
This current will flow through the 4Ω resistor.
Final Step : The current flowing through the 4Ω resistor is 1 A.