Just start by finding some refugees and their host families! Most face-to-face lessons are organised locally and aren't often promoted online. Many started as tea or coffee drop-in sessions. I would suggest finding out who is hosting families in your community and asking what you can do to help or get involved. Please ask what is being done for English-speaking practice and offer to participate or start something, however small.
This requires people to take the initiative as there is no national response to teaching English to adults, only their children. You will need a basic DBS check (safeguarding), especially if children are routinely involved.
You can also try contacting your local council or check with the following: Ukrainian Societies, adult learning centres, libraries/Village Hall info, Church/Parish reps, refugee organisations.