Nenu.

Nenu Dinesh. Ela unnaru? Nenu nitho matladuthunnanu. me peru meiti? vel irandi!

Na peru Dinesh. Meeru ela unnaru? Nenu meetho matladutunnanu. Mee peru emiti? Velli Randi.

Meeru is formal and 

neeto, neevu are informal and less polite. in starting stage i would suggest you to use formal and polite words.

Nenu.
Nenu Dinesh. Ela unnaru? Nenu nitho/meetho matladuthunnanu. me peru emiti? velli randi!

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</em>

<em>Nice work!</em>
<em>Seeing the flow of the sentence, I would suggest using "meetho"(formal) but not "nitho/neetho"(less formal)</em>
<em>I think the ones I corrected (green ones) were just typing mistakes.</em>

Nenu Dinesh. Ela unnaru? Nenu nitho matladuthunnanu. me peru meiti? vel irandi!

Naa peru Dinesh,

ela unnaru?

nenu meetho maatladutunnanu,

mee peru emiti?

Velli Randi.