It is very easy to convert base 8 to base 2. Each digit of base 8 corresponds exactly to three digits of base 2

For example, consider 365 (base 8).

3 --> 011

6 --> 110

5 --> 101

So 365 in base 8 would be 011110101 in base 2 (and you can drop the leading zero).

Have a look at this webpage below. Enter your base 8 number in the base 8 slot and hey presto it shows you the base 2 in base 2 slot.