software project

I would suggest considering what part of technology and development you are passionate and genuinely interested in. This will help you from getting bored with or giving up on the project. It will also help you focus your creativity. I would also look at some open source sites and see if there are any projects that you can join and contribute to.

Why "C" explicitly ? Even driver are built with "C++" (hum, with Windows DDK and with care but it comes up).
Do a great C++ article on Code Project, for example at this date there is not much buzz on GGL[^], and no CP article on it, be the first !
Good luck.

It's depends on your time & experience.

OP wrote:

i want do a minor project in C

Simple Bank Machine with ATM SIMULATOR
Inventory system
Phone book/Address book
Calculators
Games (like Tic tac, snake, sudoku, bricks, race, etc.,)
Payroll system
Simple accounting system