Help me out to find a good Concertina as Beginner

English concertinas have a gentler sound which some Irish musicians don't like, but they are chromatic and can play the same range of notes as a violin in first position with a couple of notes more. Though they are not traditionally used for Irish music, it's easier for someone new to play a wider variety of tunes in different keys and with accidentals. I know because my husband plays Irish music on an English concertina.

People wanting new instruments have a choice of 'Jackies' which are made with accordion reeds and are looked down on by experienced English concertina players, or else they have to buy an older reconditioned instrument.

I wish you luck in your quest, though it seems strange to be asking the question on a violin forum.

https://www.concertina.net/forums/
is a concertina forum which might help you.

The Session specialises in Irish Traditional Music and has members mainly in the UK, Ireland, and the US and Canada.
https://thesession.org/discussions

Yes - you should be asking this question on

https://www.concertina.net/forums/

Standard beginner concertinas don't give a very authentic experience and will only hold you back. Better to invest in a premium beginner instrument like this:

https://www.youtube.com/watch?v=HJKRr6nGoMw&t=3s

And be sure to listen to Caitlin nic Gabhann:: https://www.youtube.com/watch?v=Z2z8V4zZ7bs