Can I contact someone who is out of my organization and most likely a simple user (free version)?

I am a freelancer and I want to see if teams is right for me. I am on trial of business acount. Can I add people outside my organization to teams? Which most likely do not have a business microsoft account and are ordinary users. I want them to have acces on chat, maybe on file sharing and meetings with just me and one guest. Thank you very much for your time.