Hello, I have question concern how to upload my own font. I designed couple days a ago and I want to to used for my college projects. please if somebody can help me with this, please be free and add your comments. thanks

Hello, it's because you submitted a PNG graphic, not a font.

To be usable as a font, you can create a TTF or OTF file with your graphic creation.
(you have do a very nice work )

I made a font with Adobe Illustrator CS6. Is theere a way can be submit?

If you want to submit it, you have to create a font file first.
You can use Font Creator, Fontlab, Fontforge,...

I have a own font and i want to upload here

=> https://www.dafont.com/submit.php