Hoy es la noche de brujas, y aunque la pandemia ha devastado nuestro país, estamos intentahaciendo nuestro mejor esfuerzo para crear un ambiente salvno para todos.

Primero, la mayoría de las personas ha creado un sistema a dispersapara repartir dulces a través de una mesa o un túnel, ambos sin contacto.

Segundo, muchos niños no saldrán esta noche, y estlos que sí llegvarán máscaras con la ropa aterradora.

Estoy nervioso, pero no estoy muytan preocupado.

Constantemente me pregunto -¿Qué debería hacer para que todos estén a salvo?.

Me quede a casa esta noche y rezo para que todos estén bien.

¡Hoy es la nNoche de bBrujas!

In Spanish, holidays and festivities are capitalised.

Hoy es la nNoche de bBrujas, y aunque la pandemia ha devastado nuestro país, estamos intentado nuestro mejordando lo mejor de nosotros para crear un ambiente salveguro para todos.

"intentando nuestro mejor" is a word-to-word translation of "trying our best" or "doing our best". In Spanish one could say "estamos haciendo nuestro mejor intento", but "dando lo mejor de nosotros" sounds more natural here.

In this case, "seguro" is more fitting when talking about a safe place. We would use "salvo" with idioms like "safe and sound" ("sano y salvo"), or as an adverb when talking about being out of harm's way ("los niños están a salvo").

Primero, la mayoría de las personas ha creado un sistema para dispernsar [o repartir] dulces a través de una mesa o un túnel, ambos sin contacto.

"Para" is a more suitable preposition since it indicates purpose.

Segundo, muchos niños no saldrán esta noche, y estpero aquellos que sí lo hagan, llegvarán máscaras con lay ropa aterradora.

Because you are talking about two opposing groups of children, the sentence would sound better with an adversative conjunction ("pero").

Also, "sí" here is used as an adverb. In order to state an action, one is required to use an object pronoun and the verb "hacer" ("lo hagan"), which in English would correspond to the phrase "but those who do, (...)".

Tercero, los gobiernos de muchas ciudades han dicho que quieren que la gente se quede en la casa.

This sentence is perfect. However, it would sound more natural if you get rid of the article in "se quede en la casa". Because you are talking about any house and not just a particular one, the article isn't that necessary. You could as well use the possessive pronoun "sus". In that case, you must pluralise the noun.

Estoy nervioso, pero no estoy muy preocupado.

This sentence is perfect. However, the second verb isn't required. Repetitions should be avoided.

Constantemente me pregunto: -¿Qué debería hacer para que todos estén a salvo?.

There are several paths to follow here. If you want to introduce a question, you can either use a colon or quotation marks. If you don't want to use these punctuation marks, you can get rid of the question marks, thus having an indirect question. If you want to use a dialogue dash, you should introduce a line break.

Right after a "?" or "!" sign, there shouldn't be a pariod.

Me quede aaré en casa esta noche y rezoaré para que todos estén bien.

There is time shift with the verbs here. "Quede" is the 1st/3rd person singular present subjunctive form of "quedar", and "rezo" is the 1st person singular present indicative form of "rezar".

Because you've been talking about Halloween having place "today", future tense conjugations are required here (even more when you are stating plans). The subjunctive mode in Spanish is used to state wishes, doubts, probability, advise, willingness, etc.