Hello, this is Julia.

It's so nice to know and join PSM community.

==> It's so nice to know and join the PSM community.

I am preparing to go abroad to study English.

I hope that I can fine a good teacher and improve my English.

==>  I hope that I can find a good teacher and improve my English.

Thank you.

Well done~ Except for some very minor errors, you did a great job in constructing your sentences. Your errors are as follows:

article: Add the article 'the' before the name of a community, club, etc,  especially if it includes the word 'community' or 'club' in its name. (ex: The Breakfast Club, The English community..)

spelling: Check the spelling of the word 'find'.

I hope the suggestions will help! Keep posting~~