Btw Trikes

Ive been in graphic design for some time now and I always did my drawings on paper.

I want to know what program I can use my computer to make drawings on my PC and laptop.

BTW most of the things I design cars, motorcycles, quads, trikes and other stuff like that.

You can buy Autocad engineer for design. But if it's for graphic design, you can think in Adobe Photoshop.
Autocad about $ 800 or more.
Photoshop can be $ 450 +. Both are the best in their segment.

attract more Serif is very good and value for money and a help forum.