There is no upgrade method to go from 5.6 to 5.7 or Version 8.
It is possible to migrate content from 5.6 to xml files and then import those content files to 5.7 or Version 8, but it is not always successful.
5.6. sites can be upgraded to run on the latest version of php (7.4), so if you are wanting to upgrade because your server is switching to php 7 then that is an option.

Hi David,

Thanks for reply

can you please suggest that how can i run my concrete5 version 5.6.3.3 into php7.x.

because i have already tried with php7.0, php7.1 and php7.2. but that's not working.

1) bellow error with php7.0
"Fatal error: Uncaught Error: Call to undefined function mysql_connect() in .../concrete/libraries/3rdparty/adodb/drivers/adodb-mysql.inc.php:442"
" [internal function]: Concrete5_Exception_Handler(Object(Error)) #6 {main} thrown in .../concrete/libraries/3rdparty/adodb/drivers/adodb-mysql.inc.php on line 442"

2) below error with php7.1
"Fatal error: Cannot unset $this in .../concrete/libraries/3rdparty/adodb/adodb-xmlschema03.inc.php on line 178"

3) below error with php7.2
"Fatal error: Cannot use 'Object' as class name as it is reserved in .../concrete/libraries/object.php on line 3"

Thanks in advance

I offer to do this as a service, see my profile.
If you want to try this yourself, I would advise you to carry out the upgrade to the files, addons, themes and database in a local development server and when it is complete replace the files and database in your live server from your local server.
5.6.3.3 will not run on php 7, you need to upgrade to 5.6.4.0 as a starting point.

Hi David,
Yes sure, thanks for suggestion.
lets first try my self

Thank you