I have created my own fonts before but without the help of a computer. Purely mechanical using pen and ink.

Adobe illustrator would be a suitable software to create the form of individual characters and numbers.

To make it into a usable font you can type with, that I have no idea.

I'm guessing you probably need to send your newly created fonts to a font foundry for them to make it into a true type font.

They might even buy it from you if they like it!