Any film photography enthusiasts feel like answering some total amateur questions for me?

I got a contax t3 for Christmas and after some VERY bad rolls—I’m really looking for improve. As you know, its a glorified point-and-shoot. The only adjustments available are aperture, manual focus, and exposure compensation. Oh and I’ve only shot in Portra 400 (judge away)!

It’s nearly impossible to get a bad photo in daylight, so unless I’m going for a portrait or landscape lewk, I rarely touch the aperture options and shoot on P (auto mode). I have my rolls scanned at a nice place, the owner is really knowledgeable and helpful.

I’m just telling you this so you don’t think I’m taking my film to CVS. Issue # 1: the image is not as sharp as I’ve seen from other contax t3s. I’m wondering if this is a me problem, a camera problem, or a scanning problem? Or maybe I’m just not used to film grain?

Issue # 2: night time/ indoor shooting. Man oh man do my pictures suck. Would an external flash help? Do I need to tinker with the exposure compensation?

My lovely friend took this photo of me (pre-covid). I think it’s pretty nice but is there a way to avoid a) level of noise and b) “blurry” facial features? Also, is my face overexposed? Can’t tell! Help! *its not blurry but, no super sharp?

Ok, DONT LAUGH (this is the first photo I ever took). What is happening here?! help!