Is After Effects capable of rendering hi res animations based on a low res projects?

Aside from what Rick already said, you may find that doing tutorials potentially already requires lots of screen estate to accommodate everything. You may have to re-arrange the workspace, show and hide properties and palettes, zoom into details to read texts and expression code and so on. If in such a scenario you have to worry that your computer can even handle it, then there's perhaps not much point to it. You will find that for those reasons alone you will have to work with full resolution or even oversize items a lot of times because otherwise neither your nor your audience would be able to see anything. Of course there is always ways to use proxies and manually replace stuff, but most of the time it will not be worth the extra effort, anyway. Trying to optimize your process may be more complicated than just chewing through it and accepting occasional slowdowns. On the bright side, though, very few tutorial types will require 4k and HD is still plenty for such stuff.

Mylenium

First, there is absolutely no reason at all to create tutorials at 60 fps. Nobody will see the difference. It's not required for most projects and just bloats your file size.

Second, if you scale raster images or footage (video, pictures) up 200% there will be a quality loss, but then again, if you post videos on YouTube, then will be re-rendered to at least 3 different resolutions and delivered at the frame size that matches the bandwidth of the user. Unless a user has a very high data rate, the videos will be delivered from all streaming services at the highest quality that YouTube determines will be easily sent to the user. They do this because they want to make money, bandwidth costs money, and they want to deliver content quickly to the users. If you had 10,000 subscribers you would be lucky if 20% of them had the bandwidth to automatically receive 4K video. Change the frame rate to 60 and the users that would see your video at 4K and 60fps would probably drop by another 50%. The refresh rate for almost all monitors is 60Hz if the power is 60 Hz (NTSC countries) or 50Hz if the AC power is 50 Hz (PAL Countries) and most Screen Capture software defaults to no more than 30 fps, so it is hard to screen capture at any higher frame rate. I only use 60 fps (59.97) if a client demands it because 99.99999% of my audience can't see the difference, I don't make videos that people analyze one frame at a time, the motion blur at 30 or even 24 fps matches the movies we are all used to seeing, and the projects just look better. A constant dose of high frame rate video game graphics actually gives some people headaches and I don't like the look. My wife and I even walked out of the Hobbit in High Frame rate projection and asked permission to watch the movie in another theater that was running it at 24 because it looked more like a movie and less like a video game. Well, that's enough preaching for now. 

After digesting those facts of life, let me tell you about After Effects. If you do screen captures or use footage that is HD in your project, and you create the Main comp at HD, you can nest that comp in a 4K comp and scale it up to fill the frame, turn on Collapse transformations to improve the scaling of vector layers in the Main comp and use Detail-Preserving Upscale to help out the raster layers in the comp.

After Effects is not a video editing app. Almost all of your comps should be one idea or at most a short sequence that you cannot produce in an NLE like Premiere Pro. It's just the wrong tool for editing a video. AE is the right tool for creating motion graphics, creating animations, or doing composites (layering and effects) that you cannot create in an NLE. 90% of my comps are less than 7 seconds long. I only have more than one shot in a comp if I must do a transition using overlapping shots or images that I cannot do in Premiere Pro. 

After Effects has a long learning curve. It's is not an app you can just open and start to use for anything more than very simple effects. It is incredibly powerful. Any visual effect or motion graphics shot you have ever seen in any movie can be composited in After Effects, but it can get very complicated very quickly. 

I hope this helps. AE can help you with your graphics and animations, you should think about editing the final videos in Premiere Pro, and you should seriously think about the disadvantages of working at 60fps. Personally, I don't see any advantage at all to creating a tutorial that plays at 60fps. There may be a little advantage to working in 4K, but most of your audience is going to only see the work in HD.