How to Upload a csv file lager than 10MB on S3 using Lambda /API Gateway

Hello I am new here on AWS i was trying to upload a csv file on my bucket s3 but when the file is larger than 10mb it is returing "{"message":"Request Entity Too Large"}" I am using postman to do this. Below is the current code I created but in the future I will add some validation to change the name of the file that being uploaded into my format. Is there any way to do this with this kind of code or if you have any suggestion that can help me with the issue I have encountered?

   const AWS = require('aws-sdk');
const s3 = new AWS.S3();
const bucket = process.env.UploadBucket;
const prefix = "csv-files/";
const filename = "file.csv";


exports.handler = (event, context, callback) => {
    let data = event.body;
    let buff = new Buffer(data, 'base64');
    let text = buff.toString('ascii');
    
    console.log(text);
    
    let textFileSplit = text.split('?');
    //get filename split
    let getfilename = textFileSplit[0].split('"');
    
    console.log(textFileSplit[0]);
    console.log(textFileSplit[1]);

 //   //remove lower number on csv
    let csvFileSplit = textFileSplit[1].split('--')
    
    
    const params = {
        Bucket: bucket,
        Key: prefix + getfilename[3],
        Body: csvFileSplit[0]
    };

    s3.upload(params, function (err, data) {
        if (err) {
            console.log('error uploading');
            callback(err);
        }
        console.log("Uploaded")
        callback(null, "Success")
    });
}