Could anyonehelp me to create test class for below, iamnot getting the expected test coverage.

@RestResource(urlMapping='/LeadRestGet/*')

global with sharing class NS_WS_Lead_Insert {
    @HttpGet
    global static Lead doGet() {
        RestRequest req = RestContext.request;
        RestResponse res = RestContext.response;
        //String leadId = req.params.get('existing_lead_id');
        String leadId = req.requestURI.substring(req.requestURI.lastIndexOf('/')+1);
        Lead result = [SELECT Id, FirstName, LastName, phone, Email, Company,  Lead_Source_Information__c,
         Authorization_to_contact_card_provider__c          
        FROM Lead WHERE Id = :leadId];
        return result;
        
    }
    
    @HttpPost
    global static String doPost()
    {
        RestRequest req = RestContext.request;
        RestResponse res = Restcontext.response;
        System.debug('Params: ' + req.params);
        //String temp = req.requestBody.toString();
        Lead ll = new Lead();
        ll.FirstName = req.params.get('first_name');
        ll.LastName = req.params.get('last_name');
        ll.phone = req.params.get('phone');
        ll.Email = req.params.get('email');
        ll.Web_to_Lead__c = Boolean.valueOf(req.params.get('web_to_lead'));
        //if (req.params.get('web_to_lead') == 'true'){
        //    ll.Web_to_Lead__c = true;
        // }
               
        string messagesent;     
         try {
            insert ll;
        }
        catch (DMLException e)
        {
            messagesent=e.getMessage();
        }
        if(messagesent==null)  
        {
            messagesent=ll.id;
        }
        return messagesent;
    }
}