I get the idea of "doing more weights or more reps" but.. am I supposed to do that every single time? Like, say I work out each muscle group 2x a week. Am I supposed to add more weight on the second day of the week?

Should it look like: Lift 100lbs on Monday, rest, then on Wednesday I lift 110lbs, rest, then Friday I go to 115lbs, etc...

Or is it more of a week to week thing? Week 1 do 100lbs, week 2 do 110lbs, etc., And, if so, wouldn't/shouldn't that lead to someone lifting like 1,000lbs by the end of the year?

Also, "training to failure." What exactly does that mean?

Again, explain it like I'm 5. I'm sure this is shockingly easy to get but for some reason I have a mental block on it.