By using All-in-One WP Migration plugin we can easily take the backup of a website in WordPress. Just simply install the plugin and activate. Now click on All-in-One WP Migration > Export. Now Click on Export to file. Once your .wpress file is generated then you can easily import this file to your live WordPress setup by clicking on All-in-One WP Migration > Import.
By default, you can upload upto 512 MB size. To increase the size limit you just need to do the following steps.
Now the size will be 4gb. You can upload up to 4 GB. Good Luck!