We need static "Authorization: Zoho-oauthtoken" to integrate Zoho apis

We need static "Authorization: Zoho-oauthtoken" to integrate Zoho apis

We are developer. We have created a form into our website and need to capture users' information from this form into ZOHO CRM as LEADs. 
We have found api to insert into LEADS,
https://www.zohoapis.in/crm/v2/Leads.

We need to set header to access api.
$headers = array( "Authorization: Zoho-oauthtoken 1000.d402d1455512bce0a1abeb90e6b4d0fc" );


Problem is with authorization token.
To create auth token, we found this way. 
Click on <a href="https://accounts.zoho.in/oauth/v2/auth?scope=ZohoCRM.modules.all&client_id='.$client_id.'&response_type=code&access_type=online&redirect_uri='.$uri.'">Get access Token</a> , and response code will be sent to redirect url, and using that code we get auth token.

But we need auth token without clicking any button. Or we need static auth token to put into header that will work with every api. So that we put this auth token into code and program will work to insert user information into Zoho.


Thanks & Regards