You've played the tied rhythm on the left before. The two tied eighth-notes / quavers add up to a quarter-note / crotchet, so you could also write this pattern as in the lower version. The two versions sound the same and either is correct. Although you wouldn't normally write a quarter-note starting in the middle of a beat, this rhythm is so common that we make an exception to the rule.
The rhythm from above appears ten times in this piece.
Clap and count the rhythm first.
Aim for 132bpm
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Now try notating something with the same pattern in it. Again, you decide what the key and time signatures should be.
If you notated this in 4/4 but with the same notes and note values, that's fine - it's often hard to distinguish between 2 and 4-time. The piece is in A minor so it doesn't need a key signature. (A full explanation of this is in Toolkit2).