The straight answer to "Can you play roulette online?" is found at the wheel. Roulette looks like pure chance, and it is, but the rules still decide how much any bet costs. A European wheel has one green zero, an American wheel adds a second, and French tables add rules that return half of some losing bets. Knowing which wheel is in play, what each bet pays and what the zero takes is most of what there is to know about playing roulette well.
No strategy can beat roulette, because every spin is independent and every bet carries the same edge. Betting systems change the size and rhythm of stakes, not the odds, and no pattern makes it possible to predict the next number. A player can still be good at roulette in a narrower sense: choosing a single zero wheel, sticking to a budget and knowing when to stop is how to play roulette effectively. Can anyone really win? In a session, yes; over many sessions, the edge does its work.
Speed matters as much as the edge. A busy live table manages around forty spins an hour, while an automated wheel or an online game can run several times as many, and each spin charges the same percentage of whatever is staked. Whether roulette is worth playing depends on treating that cost as the price of entertainment: at a slow table a fixed budget lasts an evening, at a fast screen the same budget can be gone within minutes.
Call bets are placed by name on French layouts; the neighbours bet covers a chosen number plus the two pockets either side of it on the wheel.
Licensed wheels are tested and balanced, results are logged so bias would show, balls are made to a standard, and electronic machines use checked random number generators.
On a single zero wheel the chance is one in thirty seven, and on a double zero wheel one in thirty eight for each green pocket.
Systems only alter the size and rhythm of stakes; every spin is independent and every bet keeps the same edge, so no pattern predicts the next number.