How do I build belt turn table conveyor

It depends on which tools you have to use.

As Robert suggests, there are multiple ways to make this part. No way is really better than another, but they make use of different features.
I'd also make it with a Sweep feature. But doing so is likely the more complex way.

The "drawing" provided does not seem to give enough information, I just left some of the sketches under defined.
Image attached with the steps.

A second image is attached showing an alternative construction method.

It comes down to the goal and purpose of the exercise. If you only need a " pretty picture " , a start point would be one of the options outlined by FredSWUG, will get you started. If you need a working manufacturer-able conveyor it becomes a much more complex task. This is an engineering project, a specification of exactly what the conveyor is required to do then becomes the start point. As the wording in your question is " I need to build a belt driven turn table conveyor " , suggests to me you are looking towards a proper engineered solution. If this is so, this would be a very difficult task, if you do not have the basic knowledge of designing and engineering a practical working conveyor.

A good place to start would be a web search for information about designing conveyors. I have done a quick search and came up with these links
https://dyno.co.nz/products/powered-roller-conveyors/ - this is an option of using powered rollers instead of belts
https://www.911metallurgist.com/blog/designing-conveyor-system
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=2ahUKEwjF4_2ol7DfAhUIbn0KHU14Ca4QwqsBMAF6BAgDEAQ&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DM3eXckqFOXo&usg=AOvVaw1B3zVowxpENbFN_wNBM8DA
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&uact=8&ved=2ahUKEwjF4_2ol7DfAhUIbn0KHU14Ca4QwqsBMAN6BAgDEAo&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D84kmS0DxLtY&usg=AOvVaw3_0ugsmS-rmu-s_tBw-lG2
http://www2.hcmuaf.edu.vn/data/dangnh/file/5_Fenner%20Dunlop_%202009_%20Conveyor%20Handbook.pdf
http://www2.hcmuaf.edu.vn/data/dangnh/file/5_Fenner%20Dunlop_%202009_%20Conveyor%20Handbook.pdf
http://tstvietnam.vn/Tailieu_pdf/Bang_tai/An%20Introduction%20to%20Conveyor%20Fundamentals.pdf

As your GrabCad profile is blank I have no idea as regards to your engineering qualifications or experience, so what you know about engineering design as applies to conveyors is. Taking what you have learned as an engineering student and applying this training to real world is another step up. I was lucky as in the early days of my engineering career it was normal for a new engineer to be mentored by an experienced engineer when working on your first projects

goodmorning

first of all i hope that you do understand that this design is just that and no belt can actually work this way cause o pulley limitations....

second.
If you just need to make a design sowcase there are some easy ways to do this.....
some are already mentioned by others in this post and then there is the correct way so you can also add movement on your system.

please come back to me with what you really want to do and then if you like maybe i could help you.