https://studyspanish.com/verbs/lessons/pretserirdar.htm
Preterite: "Ser," "Ir," "Dar," "Hacer". Many verbs in the preterite are irregular and must be memorized. There are three very effective methods for learning these verbs: practice, practice, practice. Note: This is not a typo; ser and ir do have identical conjugations in the preterite! Practice Spanish verb conjugations.

https://www.youtube.com/watch?v=xkev06YaWtQ
Are you confused about when to use 'ser' and 'estar' in Spanish? In this quick and easy guide, we'll break down the differences between these two essential v

https://blog.thelinguist.com/ser-vs-estar/
Ser refers to what you are sort of permanently, a girl, an American, a Doctor etc., whereas estar refers to a temporary state of being, like being happy or anxious. But things are not quite that easy. You can find lots of detailed explanations on the use of these two verbs in books or on the web. But be careful.

https://www.thoughtco.com/learning-those-pesky-irregular-verbs-3078334
Its conjugation is irregular, too. "Am, is, are" are all forms of the verb. In Spanish, the verb "to be," has two forms that are both irregular. Let's look at one form, ser, which is the permanent form. The conjugation is not regular, and like English, the forms must be memorized. An example of ser translated into the indicative, present tense

https://www.teacherspayteachers.com/Product/60-Spanish-I-Spanish-Conversation-Practice-SER-vs-ESTAR-Cards-11696657
Enhance your Spanish language skills with our comprehensive set of practice cards designed specifically for mastering the use of "ser" and "estar." This set includes 62 sentences where students choose between "ser" and "estar" and conjugate the chosen verb in the present tense. Each sentence also in