hey guys
which one do you think should be more expensive if I'm going to record using audio interface with a mic connected through it with a XLR input?
I think the mic because it's the one that's getting the sound(I think)

but in an another situation:
is all the audio interface in the price range: 70$-90$ have the same quality?
if I'm using a reaper and an amp simulator so the FX are from the computer so the audio interface job is just connecting the guitar signal to the PC so does it really matter to have a a really expensive audio interface?
you need an apollo and protools and a slate preamp if you EVER want ANY kind of an "OKAY" sound from a mic into your computer. also you need vocal lessons for at least 18 years if you even want to get close to ever being able to talk without sounding stupid okay
modes are a social construct
It depends what kind of guitar you're recording. If you're recording an acoustic guitar, you'd likely be best off with a condenser mic, which tend to run a bit more pricey than a dynamic mic, which is great for miking an amp. It really all depends on the quality you're willing to settle with based on your budget. If I were a beginner serious about recording and will be sticking with it, I'd likely start with an interface and mic in the $150-200 each. If you're miking a cab, you can't go wrong with a shure sm57 which you can snag used for around $50 or new for $100.

In your second situation, the biggest difference between the price ranges in most interfaces is going to the be quality of the preamps and the analog/digital converters. In the $70-90 price range you mentioned, most preamps and A/Ds will be comparable, but definitely on the low end, quality wise. For anyone just looking to record some jams/demos/covers/etc, plugging a guitar DI into a cheap interface and then using plugin amps is more than enough.

Check out the interface sticky thread, there's lots of info about different entry-level interfaces in there.
Let's party.