I was told it is haram?

anyway, It depends on your trainer, as well as your body mass index, speed and agility

You will want to first train for fitness,tons of cardio!

Then agility.....you need to be able to fight a couple of rounds without passing out from loss of breath.lol

Then technic, Learn your opponents strengths and weaknesses...this is probably the hardest.

Learn your own strengths and weaknesses....I was better at a one punch knockout, if I land one right hook to your head....you will be going down...but...I was knocked out 3 times only, by 3 men half my size and strength, because they would land 20 hits to my one! and they really kicked my a**!

Learn humility, if you think your the best and cannot be beeten.....you will never win...I learned that the hard way.

Always relise that you can and will lose.

Train your mind first.

And be careful friend, my cousin was a heavyweight fighter and now at 38 has massive head injury problems, he can't think or talk right anymore, your head was never meant to take a beeting like you will recieve.

Look at a video of Muhammad Ali after his career he could barely remember his own daughter was, truly sad.

Use boxing only as self defense and or training and exercise....please.

God be with you brother.