but some themes is not working in current version.
‘Some themes’ is not a BP issue it’s a theme issue, BP developers develop BP in harmony with WP thus you always use the latest version of BP with the latest version of WP.
@bonaish try using Theme Check to test your chosen theme against the latest WP good practice:
https://wordpress.org/plugins/theme-check/
Then if you see lots of red flags then you can report them to the theme author. They’ll probably appreciate it as they can iron out any bugs they don’t already know about.