Yes, you can sell what you make from these.

Sell as many as you like — At markets, in a shop, online, wholesale. There is no number at which this stops being allowed
No licence and no fee — Nothing to apply for and nobody to tell. If a pattern requires that, it is worth asking why
Credit is welcome, not required — "Made from a Thread Craft pattern" is kind and it is not a condition of anything
What you can't do — Share, resell or reprint the pattern file. That is the one line and it is the only one
Teaching from it — Yes, if every student has their own copy. Group rates exist for exactly this — ask rather than photocopying
Why it's this generous — Because a pattern that can't be used for a living is a hobby purchase, and most people buying these are trying to make a living

What you need to be able to do — Named as actions — sew a curved seam, read a schematic, decrease evenly. If you can do those, you can make it
What it will teach you — Also named. A pattern that stretches you by one technique is the best kind and it should say which one
What it assumes — Nothing about equipment beyond what's listed. No pattern here needs a machine most people don't have
How long it takes — In hours of actual work, not in evenings. Evenings vary and hours don't
Where people get stuck — Named, with a photograph. Roughly the same two steps for everybody, and knowing that in advance halves them
If it's too hard — Say so and you'll be talked through it, or refunded. Neither of those has ever been a difficult conversation

It's linked inside the file — So it still works if you found the pattern years later, from somebody else, on a computer you've since replaced
Corrections go up within a day — Not at the next revision. A person halfway through a sleeve cannot wait for a quarterly update
The file updates free — Forever, at the same download link. You bought the pattern rather than one version of it
You get an email — If a correction affects something you own. Only for that — the list is not used for anything else
How many there have been — Eleven across nine patterns. A designer claiming none has either three patterns or a short memory
Found one? — Tell me and it goes up the same day with your name on it, unless you'd rather it didn't

You can substitute — Almost always. What decides it is not the label on the ball or the bolt, it is one measurement
Make the tension square — Everybody skips it, and the person whose jumper came out wrong is always the person who skipped it
Make it big — At least 15cm, and wash and dry it the way you'll wash the finished thing. Half of tension problems are laundry problems
Then do the arithmetic — If your square is wider than the pattern's, go down a size or a needle. That is the whole calculation and it takes a minute
For woven fabric — Weight and drape matter more than fibre. A stiff linen and a soft one behave like different patterns
If you're not sure — Send a photograph of the square with a ruler on it. That question is answered free and it is asked constantly