I'll help you out with some of the requirements.
Preterite tense conjugations for -ar verbs:
yo = é
tú = aste
él, ella, usted = ó
nosotros = amos
vosotros = asteis
ellos, ellas, ustedes = aron
Preterite tense conjugations for -er and -ir verbs:
yo = í
tú = iste
él, ella, usted = ió
nosotros = imos
vosotros = isteis
ellos, ellas, ustedes = ieron
https://www.spanishdict.com/guide/spanish-preterite-tense-forms
You can use that link for some help. Keep in mind when it comes to preterite there are tons of irregulars, so you can use the same website to find the conjugations of each verb.
Opinion starters:
Creo que... (I think/believe...)
En mi opinión... (In my opinion...)
Comparsions:
(Noun) es más (adjective) que (noun) = (Noun) is more (adjective) than (noun)
(Noun) es tan (adjective) como (noun) = (Noun) is as (adjective) as (noun)
Superlatives:
You could say "el más" or "el menos" (while changing pronouns accordingly) to express superlatives. El más means the most and el menos means the least.
You can also add ísimo or ísima to adjectives to express that it is extremely like that adjective.
Some more help: https://www.spanishdict.com/guide/superlative-adjectives-in-spanish
