Здравствуйте, а подскажите как зафиксировать длину любой детали?

hello Sir, hope you are fine , please i need some help , ... i need to knew ho to set parameters of assembly drawings for a good presentation , ... i see som exempls of asembly drawing made with the russian company topengineer, and i'm very impressed with their quality of their presentation , i wnat to present my plans like them, thank you for your help,