Translations

I want to add language element in form for multilingual support and accessed in submit handler and saved into database.

Here is my custom module file

anyone who knows how i can fix this ...
any help is much appreciated

I have a custom module which is used to insert the data related employees but i need to translate that data into hindi language as well but i didn't know how can i do that as other content type automatically have translate tab where data can be inserted in different different languages. can anyone help me how can translate my custom module data. Here is my custom module file:

For example the following template code:

<h3>{{ 'Translate this'|t }}</h3>

The source language is set to English so the text 'Translate this' can be translated to another language and edited through the UI by an administrator. However, the original string 'Translate this' can not be changed to i.e. 'Translate me' by the administrator. If it needs to be changed it must first be changed in the template and then translated through the interface (even if the translation still applies).

I have a Drupal 8 site with version 8.2.3. I have two languages configured on the site. Default - English and other one Spanish. Issue is site content is getting translated randomly. Spanish content is seen on the site when the current language is English and vice-versa.
After rebuilding cache (Drupal cache as well as serve cache) , it works fine.
I didn’t get any way to reproduce this. Translations changes randomly and it affect different entries every time it happens.

Following are the observations -

Is there any way to provide different node id's per language for the frontpage setting?

We need a different frontpage for a specific language. In D7 this was easy, we could just set a different node per language...

I've been looking for an easy solution in D8, but without luck.

Thanks!