@Noor.Money, Steemit may not currently have a built-in way to invite friends, people, currently, as far as I know, through searching for usernames, ID names, like you might find on maybe Facebook and other social networks. But on Steemit, people can follow you and you can share this post by clicking on RESTEEM (AKA share) and then your followers (AKA friends) may and might maybe see it, to see this post here, for example. Now, Steemit is an application of the STEEM network but there are other applications too, like http://Busy.org and maybe Busy has a way to invite like in what you want to do or maybe http://Steeming.com has it or maybe other websites (AKA applications of STEEM) may have what you need and you can Google this and find it. You can find so many things and answer so many questions through Google and DuckDuckGo and more.....