THERE IS FAR MORE to analog circuits than just the world of operational amplifiers, (op-amps).
The TS will be very poorly served if that is the limited area of study and understanding.
Packaged function blocks are very handy and they are certainly useful, but understanding what is going on is useful for those instances where an exact answer is not provided by others.
Little details such as understanding the differences between different models of ICs and the reasons for power ratings of resistors can avoid a lot of things going wrong.

 

Like the 5-point palm exploding MOSFET problem?

 

agreed for op amps, allaboutcircuits.com web rather good place to start
https://www.allaboutcircuits.com/textbook/semiconductors/chpt-8/introduction-operational-amplifiers/
op amps are somewhat 'simpler' than arbitrary raw electronics such as diodes and transistors.
op amps made otherwise non-linear behaviours linear - sort of.
but real world op amps are imperfect, e.g. CMRR (common mode rejection) only works up to some voltage.
This in part as both the + and - voltages are highly amplified, at some point, physics kick in and it is impossible to make it look as linear as a perfect straight line.

the concept of an op amp, is pretty much worked into how those cheap 3 pin voltage regulators work
https://www.petervis.com/electronics guides/voltage-regulator-using-op-amp-and-transistor/voltage-regulator-using-op-amp-and-transistor.html
these days for the convenience and lower costs, few bother to go the distance to make an op amp voltage regulator, instead ready made regulators cost much less, is mostly 3 pins, has all the engineered detail specs that simply promise you milliamps, much easier.

 

Op Amps are indeed wonderful little building blocks, and they are very useful. But it it is very important to know how to read and understand the specifications, and how to interpret the data sheet. An understanding of the value of the application notes for opamps is also very handy.