How does the present or past tense work in german?

[regal saffron]

Like, if i want someone to know what a person a doing in the past or present, how do i convey what i am talking about. For example. "Er trinkt bier"
This can both be "he drinks beer" or "he is drinking beer".

[strange dove]

Yes, that's correct. If you want to convey the man is drinking beer right now, as we speak, you'd add "gerade": Er trinkt gerade Bier.

[regal saffron]

Can that word be used for most situations i.e Sie spielt gerade guitarre or anything similar

[strange dove]

*Gitarre - yes, exactly.

[regal saffron]

And if i forget to use the word "gerade", it can convey the same meaning regardless yes?

And also, do you perhaps know of any site that has the most spoken german words?

[strange dove]

Googling something like "frequently used German words" will render lists. Those will be of very little use to you, though - think of English, the most frequently used words are words like "are, is, the, a, an, will, am, to, do, going" -> learning those isolated forms will be of very little use to a learner. ;)

[strange dove]

Yes, of course. It will depend on context.