The developers and users of that plugin would be the best people to ask. You can reach them here:
https://wordpress.org/support/plugin/wp-survey-and-quiz-tool
Unfortunately, it appears that plugin is no longer supported.
there is no any way to edit it from the WP Dashboard?
Typically no, unless you consider the plugin editor part of the “Dashboard”. That can be a dangerous way to make changes, we advise against it. If you choose to use this anyway, please deactivate the plugin before making changes. It’s better to make changes to a downloaded copy after making a backup, then uploading it back to your server.
We are not familiar with that plugin, which is why we referred you to the dedicated support forum. We always advise changes to plugin code be done through filter and action hooks. Directly altering plugin code can be problematic, but considering the lack of support, it may be a reasonable approach. You’d need to locate where the button text is defined in source code, then change it.
If by chance the button text goes through the apply_filters() function, you should alter it by adding your own filter instead of directly altering the text.
