This is the best plugin I see for that:
https://www.roblox.com/library/143613186/Model-Resize-Plugin-2-1-DRAG-TO-RESIZE?ViewInBrowser=true&CreatorId=3925445&SearchId=27CA40E4-2930-4118-90DA-063C51E5C1F0&Category=Plugin&Position=13&SearchKeyword=&CreatorType=User&SortType=Relevance