Hello, @Ajit Terdalkar, my suggestion is to reduce the size of the attachment. The simplest way to do this is to compress the file or split it into several files.
It is even simpler to upload your file to any cloud and just to give the link to the files to download. Here you can find more tips on the workarounds concerning your question, such as getting a bigger limit with iCloud Mail Drop and compressing your attachment in a ZIP folder.
If you are serious about data safety, I recommend visiting this useful link, if you want your important Microsoft 365 data to be recoverable in any unpredictable situation.