astronomy - Absorption lines in the context of identifying

I understand that absorption lines are used to identify elements but how are individual absorption spectrums identified in the light that is received by a telescope?

Types of Astronomical Spectra

Kirchoff's Laws and Spectroscopy

Ask Astro: How do scientists determine the chemical compositions of the planets and stars?

Chapter 05 Mastering Astronomy Flashcards

Chapter 17 Section 17.3: The Spectra of Stars (and Brown Dwarfs) – Survey of Astronomy

Spectral Lines

Spectral Classification - Hertzsprung-Russell Diagram - NAAP

Measurement of neutral gadolinium oscillator strengths using dual-comb absorption spectroscopy in laser-produced plasmas - ScienceDirect

5.3 Spectroscopy in Astronomy – Douglas College Astronomy 1105

Ask Astro: How do scientists determine the chemical compositions of the planets and stars?

Using Spectra To Find Life Elsewhere In The Galaxy

Solved Problem 5. (Measuring receding speed of galaxies.] We

Emission and Absorption Lines

Absorption spectroscopy - Wikipedia

A highly magnified star at redshift 6.2