I was using the domain “5avblog.wordpress.com” and I was not able to install any plugings, so have purchased a personal domain “5avblog.com”. But I don`t see the possibility to place plugins in my web page.
Can you help me?
You need to find and pay a company to host your site with the domain name your purchased. You can use the free software from WordPress.Org to make your site work on a self hosted site with ftp access and plugin capablilities.