## 1 Introduction  
Gaia, a project of the European Space Agency (ESA), began scientific operations in mid-2014, after a successful commissioning phase. Gaia's primary scientific aim is to scrutinize the kinematic, dynamic, chemical, and evolutionary status of the Milky Way galaxy. Through continuous sky scanning, Gaia gathers astrometric, photometric, and spectroscopic data from an extensive set of stars. The mission's ability to cover an extended region in space at many times makes the systematic identification, characterization, and classification of diverse objects easier, including variable stars, owing to the multitemporal nature of the observations [1]. The spectrophotometer is one of the key instruments on the satellite, and it consists of two photometers: one covering the blue region of the electromagnetic spectrum (BP), with wavelengths ranging from 330 to 680 nm, and another in the red region (RP), covering the range of 640 to 1050 nm. These devices generate low-resolution spectra consisting of 62 pixels each [1]. The Gaia DR3 catalog, released on 13 June 2022, represents a significant advancement in astronomical data, surpassing its predecessors in several key aspects. This release expands not only the quantity of sources studied, but also enhances the quality and diversity of the data provided. The dataset underwent rigorous validation processes to ensure its reliability for scientific use, offering an unparalleled combination of quantity, diversity, and quality in astronomical measurements [2]. For the first time, GDR3 includes calibrated spectra obtained with the blue and red spectrophotometers (BP and RP, respectively) [3]. The internal calibration process standardizes spectra obtained at different times, adjusting them to a common flux and pixel scale. This approach considers variations in the focal plane over time, resulting in an average spectrum of observations for each source [4]. While this method eliminates information on quick spectral variations, it allows for better source identification. There are some peculiar stars that are difficult to classify using conventional methods due to their unique characteristics. Additionally, the vast amount of spectral information generated by modern telescopes makes it impractical for astronomers to process such data individually. Automatic classification has become imperative in the current era, where a large volume of data needs to be handled. In its DR3 catalog, Gaia released approximately 470 million sources with astrophysical parameters derived from BP/RP spectra [5]. Modern astronomy, driven by humanity's insatable curiosity and the desire to understand the universe, is essential for developing a scientific worldview based on empirical observations, verified theories, and logical reasoning [6]. This research specifically focuses on three types of astronomical objects: symbiotic stars, planetary nebulae, and red giants. These types of objects are of interest because they originate from the evolution of low-mass stars. As detailed below, symbiotic stars are distinguished by their binary nature. However, the similarity of their spectra sometimes leads to misclassification. * Red giant (RG). These stars evolved from intermediate-mass stars (from 0.8 to 8 M\({}_{\odot}\)), with a larger radio but lower surface temperature. As stars like our Sun evolve, they deplete the hydrogen that sustains the nuclear fusion occurring at their core. This causes the core to contract, increasing temperature and pressure, leading to the expansion of the outer layers. As they evolve, their outer layers are expelled in the form of low-speed winds that form envelopes around the remaining high-temperature star (white dwarf), thus becoming a Planetary Nebula. White dwarfs represent the final stage in the life cycle of stars like our Sun. They return a significant number of fusion product elements to the interstellar medium, where these elements then reside [7]. * Planetary nebulae (PN).