Upload large file by chunks using File reader using Angular

I am trying to upload files and the current code supports file size upto 100MB and if the size of the file increases getting out of Memory screen in browser

private ProcessReadFile(file:File){
   return new Promise<void>(resolve=>{
        const reader= new FileReader();
        let content:any;
        reader.onloadend=()=>{
                     content=reader.result;
                     var fileContent=content.split('base64,')[1];
                    this.fileUpload.push({
                       Filecontent:fileContent;
                       FileType:file.Type
                     });
                 resolve;
         };
     reader.readAsDataUrl(file);
     });
  }

I came across some solutions where they are slicing the file into chunks and processing. I am not able to understand and achieve with the above method.

Can some one please suggest/help me to upload large data files.