How to upload a file which type is .htm or .html and..how to limit the size whthin 100 MB?

I need to create a web which allow user to upload a file

my problem is...

1 . ListBack.aspx

user will upload their html or html file from ListBack.aspx ... How to upload a html file? and the file size must within 100 MB?

can you please give me a example for how to upload html file?

 

thank you very much
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