I want to do SEO(Search Engine Optimization), but have questions here, Do I need to host my site with the SEO provider?
Do I need to give the provider my FTP account?
If I dont do the above mentioned, are there any other ways?

Do I need to host my site with the SEO provider?

No.

Do I need to give the provider my FTP account?
If you trust them you can but I wouldn't to start off with. They should be able to either suggest changes which you implement or you could give them a copy of your source which they forward to you to upload. That way you can review it first.

At this point it's worth saying make absolutely sure you know what they are doing to your site. Their are many SEO 'experts' that do things that will improve your results in the short term but are banned by the search engines once you're found out. Read the Google webmaster guidelines and any other search engines guidelines you get traffic from as getting unbanned later is not going to be a nice experience.

If I dont do the above mentioned, are there any other ways?

DIY? the basic idea is to get as many links to your pages as possible. Preferably with the link text relevant to your keywords.

Check Matt Cutts (http://www.mattcutts.com/blog) blog for a few tips. He works for Googles webspam team so he knows exactly how their indexing works and offers some advice and insight into such things.

SEO needs to be done both on-site and off-site. If the SEO service provider needs to make changes of your web pages, they do need the ftp access to your server.

You don't need to have your site hosted by the SEO company. If that is what they tell you, run as fast as you can - they are trying to scam you.

Most SEO "experts" have no clue what they are doing. They can pull some nasty tricks to fool search engines in the short term, but causing long-term damage to your ranking. Ask for their work sample rankings. Check out references!

Best of luck!

Some SEO's can work without FTP access to your site, but it just makes the work harder because they are waiting on you to make the changes they are requesting for the site.

If you give them FTP access you have to trust them that they will only make SEO changes and will inform you of any changes before they go live.

As for hosting, you can host anywhere. They may want you to host with them so they have direct access to the site and don't have to worry about getting your FTP login, but if they are making it a requirement you may want to rethink it because it is not needed.

Thank you
I will to test it with u say

Go with a reputable seo company to leave all your worries behind!