Setting length for projects and using timecodes in Adobe Animate

I'm a beginner with Animate, and so far I've not been able to, or able to figure out how to set a specific length to a document. By default, the timeline ends at 27 seconds, but if I add frames, the timeline lengthens. Is this the only way to add to the timeline, i.e., the length of the document? You'd think Animate would ask how long an animation you want to make when creating a new document, assuming you know from the start. If you can not set a specific length for a project, then I'd really like to know why. I'd also like to know if you can jump to exact timecodes, instead of skipping around manually, or send elements in a layer to another place in the timeline using timecodes. If not, then Animate would benefit greatly from these features, and so would I.