The band on the fit broke so i just replaced it with a leather one and the small band that holds the end so it doesn't stand up broke and it's not a week old

yes
under the band at the ends there is a small spring loaded pin that is removed and the band comes out
use something with a sharp edge , press in in beside the leather and then push sideways to compress the spring and the pin will come out
or take it to a jeweller and he will remove and fit the new band in 5 minutes

Depending on the model, if it is one that has a leather strap, then they are held in place with spring-bars that go through the ends of the band protruding out of each end. the points then insert into holes in the bezel lugs and thus hold the band in place.
The best method is using a tool made for this which you can pickup at any Harbor Fright Tools store if there is one in your area. Alternatively, use a small screwdriver and insert it against the inside of the lug where the band rides against. As you begin to pry downward away from the lug, you will see the spring-bar. Look for any ridges on the bar that can be used to pry further... it's really trial and error and use caution to not damage your band. another way that works quite well is a not-too-sharp knife. Again insert it between the band edge and the inside of the case lug and with pressure against the pin, pry downward away from the lug... the ping should disengage

You would have to visit a retailer who sells watch bands and have them show you compatible bands. There are tons of universal ones, but it depends on the width of the connector where the leather band joins to the watch face, and if they have something that will fit that width. It can take them a few moments to change it out, after you've identified what fits.

If you need an authentic Disney watch band, try asking at a Disney store. However, non-Disney watch bands will fit this watch and may be both better quality and less expensive. Almost any jewelry store, department/discount store jewelry counter, or shopping mall watch kiosk will be able to measure your watch and determine the right size band. Many women's watches in this general style use a 14mm or 16mm band, but you should measure your watch to make certain.

order a replacement band directly from skagen its only $25

http://www.skagen.com/service/home.fx

I will give you the generic answer as I have not actually removed a Cartier buckle. Most buckles use a small bar called a spring bar that goes through the band and "tang". The ends of the bar are like a plunger in that with a small fork like instrument or small screw driver you can collapse the bar and move it out of the clasp. The rest is very obvious. Replacement is the opposite of removal. A fairly simple procedure for most people.

Hi there. Insert the mesh strap inside the hole and secure with the hook and clip fastening with a foldover security clasp.

Hope this one helps.

GO TO EBAY AND SEARCH PUMA REPLACEMENT BAND