Plugins, Themes, Users and Tools not shown after making a CPT with code snippets

Are you able to delete the code you added?

Maybe try following the instructions here instead
https://www.wpbeginner.com/wp-tutorials/how-to-create-custom-post-types-in-wordpress/

@janet4now I tried deleting, the whole plugin ‘Code Snippets’ of my ftp but it didn’t work.

Do you know exactly what code you changed?

As a last resort you can contact your host and have them revert to a backup version?

@janet4now I don′t have a backup but it′s not a problem because I am just trying practicing, but I guess generateWP is not a good site to create CPT′s? I tried adding the same CPT on other site with other host and this time it does not let me add a new item. I guess the problem is generateWP?

GenerateWP works fine. There is something else going on here.

Do you have debug logs enabled on your site?

Here is how you can do it.