Error in get leads from zoho crm and add leads to zoho crm

Error in get leads from zoho crm and add leads to zoho crm

Hello Team,

I got the access token from zoho in postman and able to get and add leads by postman.
but when I try to do the same from my React JS Website it give us error.

Access to fetch at  'https://www.zohoapis.com/crm/v3/Leads?fields=Last_Name,Email&per_page=3' from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
VM46:11
       GET https://www.zohoapis.com/crm/v3/Leads?fields=Last_Name,Email&per_page=3 net::ERR_FAILED 400 (Bad Request) 


Can you please help?