You want it honest?

Does this sound good?
++ NO it doesn't sound good.

Or am I stupid to even attempt such a commute without some more practice and conditioning first?
++ Yes, please get some practice and conditioning first.

The good thing is, commuting by bicycle is naturally self limiting. Meaning if you can't make it - you just won't. Try it on the weekend one day first and see how you do. You might be able to do it once every 2 weeks, and work your way up from that.