title says it all.

Can you elaborate a bit more? Are you looking for web hosting on linux? virtual linux server?

No business will usually let you use their resources for free. You can find cloud server with shell access for maybe $10 to $15 a month from some sites.

i want to use linux or unix by using putty. i dont want to download lunix or unix on to my computer. hope it helps

right. you want someone who has a server on the internet to give you shell access to a host. You can get your own 'cloud' host from a provider for a few dollars a month.