Hello people

I'm new to this forum, haha.
Now, if someone could help me, I need some predictions and a few things cleared up.
Firstly, I am starting Year 11 this year and I am studying:
3/4 Bio
1/2 English
1/2 Methods (CAS)
1/2 Physics
1/2 Business Management
1/2 Chemistry
I am aiming to study Biomedicine at Melbourne or Monash, I don't mind which one.
I was wondering ''Roughly'' what study scores I will need in these subjects, also, If someone could give a estimate about how much homework/study I must do a night.
At the moment, I am motivated, A pretty good student and I really want to do this. I haven't really done that much work in the past few years but I know these two years will determine most of my life, so I really want to do well.
These reason I didn't do too well in the past few years is because of computer games being a big distraction but I have lay'd of the games and wont play them much in the next two years.
Another thing is I have a girlfriend which I love, we've been going out for 6 months now. Is this a bad thing?
Am I still able to get into Bio Med if I have a girlfriend during VCE?
Also, should I mostly focus on getting a good score in Biology since it's my only 3/4 this year?
Also, If I don't get the ATAR required, what are some other ways to get get into medicine?
Thanks in advance for responses

P.S sorry if that's too much, I just need a few things cleared up.