Learn Russian: Я почитаю журнал, а потом посплю. - I will read a magazine for a bit, and then get some sleep.

Both are perfective verbs, but they give a different meaning. прочитаю means you will read the magazine completely from start to finish. Adding the по- prefix to читать creates почитать, which means to perform the action for a short, limited time. So почитаю means "I will read for a bit."

Does посплю work the exact same way as почитаю here?

Yes! The base verb is спать (to sleep). Adding the по- prefix makes the perfective verb поспать, which means "to sleep for a little while" or "to get some sleep." посплю is simply its "I" (first-person singular) form.

These verbs have present tense endings (like читаю). Why does the translation say "I will"?

In Russian, perfective verbs do not have a present tense. When you apply present tense conjugation endings to a perfective verb (like почитать or поспать), it automatically creates the simple future tense. That is why почитаю means "I will read (for a bit)" and not "I am reading."

Why use а потом instead of и потом for "and then"?

While и means a simple "and," the conjunction а is often used to show a transition or a shift to a new step. The phrase а потом is a very common expression meaning "and then" or "and after that" when moving from one sequenced action to the next.