I'm clueless about this kind of things and new to them. I wanted to make sure about some things before i get the sitemap generator:
1. Is is dynamic? meaning if the site has new pages it updates it automatically.
2. If so, what info do i need to make it work automatically?
3. Do i need to go over the sitemap before i Upload it? how accurate is it?
4. If i find that it didnt index some pages or indexed pages that are not good (like a second URL for the same page) can i ad or remove them? but then, in the next scan wont it add it automatically to the server?
4. Can it support non Latin languages? specifically Hebrew.

Thank you for your time.

1+2)
If you want A1SG to automatically update and upload new sitemaps when you add new pages, you will need to schedule it to run e.g. daily.
http://www.microsystools.com/products/sitemap-generator/help/automate-sitemap-build-upload/

3)
While A1SG will show you most errors after websites scan (using default configuration), the URLs found in the generated sitemaps only include valid functioning URLs (i.e. no "not found" or "redirect" URLs.)

4)
It is worth noting A1SG can discover duplicate URLs and pick the correct one to include in sitemaps. (This includes  canonical, but A1SG can also determine based on the URLs themselves, e.g. "example/" and "example.com/index.html" can be considered duplicates. You can configure this behavior if necessary.)
http://www.microsystools.com/products/sitemap-generator/help/duplicate-content-page-urls/

You will also want to check this help page about robots.txt, noindex, nofollow etc.
http://www.microsystools.com/products/sitemap-generator/help/sitemap-robots-noindex-nofollow/

5)
Hebrew is no problem at all. Do notice that A1SG defaults to URL percentage encode URLs (as that's the "standard"), but you can disable this if you want.
http://www.microsystools.com/products/sitemap-generator/help/character-percentage-url-encoding/

...

I suggest you download the trial and check it out

If you are interested in seeing full capability of options, click off "Simplified easy mode":
http://www.microsystools.com/products/sitemap-generator/help/easy-sitemap-generator-mode/
(e.g. incase you want to enable Javascript support etc.)

You can also check the sitemap tutorials:
http://www.microsystools.com/products/sitemap-generator/help/#tutorials

Be sure to ask if you have any questions!