If ”profile” means your profile here at WordPress.org, then: No. We have too many systems interacting (forums, hundreds of blogs, several trac and SVN instances, etc) with the profile for us to change the user-ID. But you can still change your ”nicename”.
If you mean the profile of your own WordPress installation, then yes, it can be changed, but for stability and security concerns this option is blocked by default. You could either do it directly in the database, or install some plugin, like https://wordpress.org/plugins/username-changer/
If i am going to change in my wordpress instalation, will it make unstable site?
No, it won’t destabilize your site. But the user may have to (re)set their password.
As always, though: It may be a good idea to save a backup of the database before attempting this.
what if i will create another wordpress.org account with diferent username. how will affect my currently website secoffin.se?
actualy i am bit confused. when i login in to admin panel to secoffin.se i use wordpress.com account. please explain me if wordpress.org account somthig do about my site or nothing. completele confused
The website WordPress.org is totally separate from any other site. Your account here is only used for these forums (and for contributing to development, translations, etc.)
Your own site has its own database, its own userbase. If it’s a small hobby site, then most probably you’ve got only one user registered there – namely yourself, as an admin.
If you’re using WordPress.com for your site, then you should have in mind that they’ve modified many bits of how WordPress looks and behaves, in order for it all to fit the services they offer. If you’re looking for support on how to use their services or how to change your ID with them, then https://wordpress.com/support/ is a much better place to ask. (In this forum, users of the free software WordPress.org help each other when they get stuck.)
Then we’ve got the middleway: If you’ve installed the plugin Jetpack on your own site, then you’ve empowered your site with some bells and whistles from the WordPress.com universe, like: login via .com account; subscribe to new posts via the wp-com Reader experience; possibility to use their mobile apps; etc.
If you want to change your userID on your own site, but are using Jetpack, then you may need to reconnect you Jetpack connection after the change. I just don’t know the details on how Jetpack maintains its connection.
Oh. In case you didn’t notice: You asked your question in the local Swedish forum. The international WordPress.org forums, where you’ve got many more volunteers eagerly waiting to help, are located at https://wordpress.org/support/ (and there you’ll also find hundreds of support articles).
very very apriaciate your help to understanding these systems. now it become more clearly. thank you very much for good explanation.
