Do you need TTL LOGIC to control the fan, OR just TTL LEVEL to control the fan?

 

I was trying to build this in a project board and i am a beginner making circuits so i am trying to have the most simple circuit that will make the ventilator work so i can cool down another project that i am working on.

So far you have specified no need for TTL. Just a switch can turn on the ventilator. To turn on the ventilator under some specified condition requiring logic would justify the TTL circuit. So far just a 74xx05, 06, 07, 16 or 17 (any open collector output) will get you the "0 to 5 V" requirement.
To turn the fan on or off depending on certain temporary events a flip flop is called for. 74xx74, or such.

 

The schematics on the link you posted are indeed the internal schematics for the standard TTL varieties that have been developed over the last 50 years. However, building them up with discrete components will not teach you anything about how TTL *logic* functions. Also, you can build up one of the circuits, or go buy a TTL gate chip, connect a pushbutton switch to the input, connect a solid state relay to the output, and when you push the button the fan will come on. BUT, again, this won't really teach you anything about what TTL was invented to do.

"circuit that will make the ventilator work" is very vague. What is it you are trying to accomplish? If you want the fan to be controlled automatically through some sensing or decision making circuit, that certainly is possible with TTL chips.

ak