Is this difference marked in Russian verbs?

e.g.

-In english the Preterite (Simple Past): I ate
-In english the Present perfect: I have eaten

So as both are Perfective in nature I would assume съел or поел in Russian (not sure which one) but alone is it correct to say that in russian the perfective can denote either of these two english "tenses" before being more strictly assigned to one with the use of additional adverbs?

Ontop of that, how would one tie the meaning to these two using adverbs? Essentially by adding уже for example?

Just making sure I have understood correctly that much like ел could represent either a habitatual action (used to eat when i was 5) or a continuous action (I was eating when the phone rang) I was wondering if this was similar in its variation before adding other words to the sentence to solidify its meaning.

SIDENOTE: I have eaten could denote both, having just eaten so being full (not hungry) but it could also be used in another way, for example:

"You are suppose to chew when you eat"
"I HAVE eaten before, you know!?"

This doesn't denote that you have eaten and are therefore full in the present, but explains that you have eaten in the past and it is now part of your experience, In icelandic for example these differences are marked with two different auxilaries "hef" (have done it before) "er búin að" (I have finished doing, i.e. recently). Is there a way to denote this in Russian?

Thankyou for you help.

(EDIT: Final note, if anyone could tell me how to distinguish between present perfect and past perfect "I have eaten (now), "I had eaten (when he arrived)". I noticed I am asking about making the PRESENT perfect using the past in Russian, but that seems to be the only avaliable option at there is no "present" form of the perfective.)