Differential drive wifi controlled robot car .

I would be happy to answer any specific questions you post.

You have the pleasure to write the code and do the learning.

You may want to start with 2 continuous servos rather than DC motors tho.

Open loop DC motors dont keep speed very well and you'd need to PWM the H bridges, or close the speed loop regulator with a motor encoder,  unless you are buying an I2C driver board with the built in functionality. 

You might be advised to start with a kit like a parallax with an Arduino controller, Probot DIY, Elegoo, etc...     

OP mentions BLDC however, which are likely to keep better speed than typical (i.e. low-cost kits containing them) continuous-rotation hobby servo's.

Question for OP: it sounds like you have something particular in mind, since you're being quite specific with the type of motor and voltage and the particular mechanical drive you want to implement, and you've even specified the particular microcontroller board. I'd suggest there's a dichotomy between that and a general learning type of project.

Plus, the chance is almost zero of finding any online educational material that would meet all your specifics.

Same as robogary says, I wouldn't pick BLDC to start off with either.

Stepper motors would be another great option, not too difficult to drive due to the variety of ready-made stepper motor controllers, and very good at keeping speed with each other. Not mega fast though (might not always be a bad thing though).

Totally agree that kits etc would be very good, to reduce frustration if you're a beginner.

On the other hand, if you specifically need to learn how to drive BLDC, then concentrate on that before you try to integrate into a larger project. That's a large enough learning curve right there.

good advice. Its tough for a beginner to get comfy with all the facets: mechanical hardware, electronic hardware, platform software & IOT. 

BTW, A big disadvantage with steppers for mobile vehicles, standard steppers are pretty heavy, even heavier than metal DC motors with a gearbox and encoder.

Thank you for your suggestion . I have worked with arduino uno  to make a simple car . I have already worked with smaller motors . Now I want to work with different development board. Since stm electronics have so many mcu’s . After researching I decided the nucleo board which will be sufficient economically for me . Is there any reson you are telling me to not start with dc motors . ? Thank you .

I am planning to add hbridge driver to pwm the motors too . That is one of the part in my project too .

Thank you Robogary , one of the information i need is about hal library for stm development board . Where can I get examples or learning courses on hal library . 

The hat usually has a published users manual, thats the best place to start.

2 DC motors on the same vehicle dont run exactly the same speed due to differences in gear losses, friction loading, etc. that is, it doesnt drive in a straight line even with perfect alignment.

If the vehicle is line following, the differential steering control adjusts the speeds ( output voltage via PWM duty cycle ) anyway, DC motors will be fine. If you are continuously providing external steering control, DC motors will be OK too.  

Continuous servos are easier to understand and write code for, thats why beginners use them.   

Thank you