If you work on Procreate I would first recommend working on the bigger size the program allows you to work on.
Another thing you could do is to save your file in PNG instead of making it smallerin JPEG which tends to lower the quality and get a bit pixelated.
Then by resizing to Tapas size I believe the issue would lie down exactly on where are you looking at the resized image, is it from pc or a big tablet? If that's the case then it'll look blurry no matter what, what matters is that it looks neat once it is on a mobile view mostly a cellphone the size of the average human hand.
But in case that your issue is not within format or device, I believe you should give a look to this thread or this video.
Personally I work with Clip Studio Paint, so originally I work at 1600px width x 30000 lenght, then when it is time to export I only set it to Tapas width (940px), I do save my file in JPEG then lower quality to 85% since the quality of art doesn't look that bad once in my phone or tablet, on pc of course it looks a bit pixelated but it's tolerable.