That doesn't look like the red maple I'm familiar with, but I don't know a lot about that species.

If your tree is healthy, I wouldn't worry about the dead tip. The tree will send the current branches up to establish new leader/s. It's up to you if you want a multi-trunked tree, or if you want to cut away some of the leaders to have a single trunk.

You mentioned growth being slow, but it looks to me like there's about to be a lot of new growth from the tips of those new leaders, so I'd wait and see how much it's grown in a month or two.

Good luck!

"I bought the right soil for maples, i water the tree everyday"

Do not water every day! Your poor growth is most probably a result of overwatering. What "right soil" did you buy?
I use a very coarse soil and water thoroughly 2-3 times a week, less if we get a good rain. You should not prune anything at this point, as the tree is young and stressed from too much water. Let it grow out for a few years, then you can decide what to do to shape the tree.

my soils is 40% silt/sand, 20% peat moss and 40% organic compost.

That's a good mix Carlos, I use "Al's Gritty Mix" modified. 25% granite grit, 25% turface and 50% pine bark fines. The normal "Gritty" is 33% of each,which is a good all around mix, but my bonsai book said JMs benefit from more organic material. It's a very coarse mix indeed, and you have to supply ALL the nutrients.

When I started using it, I watered every day, thinking it would not hold enough moisture. I almost killed 3 potted JM's because of watering every day. I water a 1-3 times a week, depending on the outside temps (once per week right now)

The watering regimen takes a bit of getting used to, but my JM's are extremely healthy, vigorous and look phenomenal!

thanks for your helpful replies :) i will follow your advice about watering =D