My first option trades - possible game changer in my portfolio strategy?

Agonizongly, I fumbled a few days with this, and I'm still not sure I got it right, but everything's got to start somewhere. So voila! I setup 2 covered calls sale on 2 positions I own.

STLA has more positive news (interest rate cut, spending on discretionary to rise allegedly) and is supported by the TA trendline for an upside, so I set the strike at 18 (current 16) dte 49. I don't mind sacrificing this even if the price shoots higher to gain some learning.

ACHR does not have TA trendline to support a growth story, some good news but not significant (but who knows what other investors will perceive the news?), good industry, bad financials. If I can get rid of it at a slightly higher than market price, well, I don't mind. 

Option trading made me mindful that I should buy US stocks in the multiples of 100 as much as I can.  That's going to be a big change.

Not sure why it says 'short sell' in the order details coz im not short-selling. Can someone help me with that terminology?

Update: sold one of the 2 almost immediately