You can't. But there is a reference to him when *Possible Spoiler* Michael talks to Lester about potential crew members for the Jewel Store Heist. Lester is the one that mentions him but not by name.
NO!
Omg, you already are niko. However on online you play as someone else and no you can't play him online.
No, there is no character customization in GTA 4, so you cannot improve Niko Bellic's strength.
No
Niko is 6 ft 3 in, Johnny is 6 ft 0 in and CJ is 5 ft 8 in.
No, Kate will finish with Niko if he accepts Deal.
No
Niko Bellic is voice acted. Niko Bellic is voiced by Michael Hollick.
No that is only in gta sa
Nope. Just a cop.
In Niko's final encounter with Jeff, Jeff is a doomed man, Niko cannot save him.
No, Niko Bellic cannot join the LCPD in GTA 4.