Good job with the plant and the silk :) Mine takes a few days to even notice anything.
You got a heater and thermometer! Yay! Watch for those preset though, less reliable. I have it also, it's... okay...Lol.
Yeah, the kits are...yeah, lol. The water changes are to keep the ammonia down to get out of hand, so yes, keep doing it, otherewise it gets high FAST. Which is the point of the frequent changes.
He'll get used to feeding, so no need to push it yet. I feed mine twice a day, breakfast and dinner. Occasionally lunch (three times) on the weekends when I'm home. I feed two pellets for each meal. He'll eventually get used to it.
The lightly is solely for personal viewing options, but YES you MUST turn it off at night. And also if you keep it on too long, algae problems occur.
Oh god, employees *AHEM*. Most are unreliable. That one right there, probably unreliable *shudders at the thought.* He never said he was a successful breeder, now did he? You definitely need everything for these. Again, fish (bettas) are not the easy way for a pet~ Good job, you're doing fine :)