first things first you have to do write it down which you did
step 2: then you multiply each digit of the binary number by the corresponding power of 2: 1x25 + 0x24 + 1x23 + 1x22 + 0x21 + 1x2 0
step 3: solve the powers: 1x32 + 0x16 + 1x8 + 1x4 + 0x2 + 1x1 = 32 + 0 + 8 + 4 + 0 + 1
step 4: add the numbers written above
32 + 0 + 8 + 4 + 0 + 1 = 45.
So, 45 is the decimal equivalent of the binary number 101101.