RT is pretty biased but sometimes they have some quality journalism. I find that's with all networks though and everyone should always check with multiple sources and not just stick to one network.
For example, I like Al-Jazeera but I wouldn't trust them to report honestly on the Qatar government. FOX is pro-Trump/Republican. CNN is the opposite but more bearable imo. RT will be anti-Western/pro-Putin. Sky News has a conservative bias. CNBC, NPR I think has a liberal bias etc.
Bias isn't always a bad thing, but you should be aware of it. Some stations are more biased than others, for example Fox News is more biased than ABC News Australia. The former is more right-wing, the latter being centre (or centre-left) however ABC (Australia) has a lesser degree of bias and a high factual reporting grade.
The sources I check with the most usually have a centre to centre-left bias, but usually to smaller degrees and highly factual reporting. However there are some I watch that are a lot more biased than other channels I watch.
Some of the least biased sources are: ABC News Australia, Associated Press, Australian Financial Review, C-Span (duh), Daily Business Review (Florida), Digital Journal, AFP (Agence France Presse), DPA German Press Agency, Eurasia Review, Euronews, FactCheck, Fair Observer, Federal Times, Financial Express (India), Financial Times, Gallup, Foreign Affairs, Foreign Policy, Harvard Political Review, Investopedia, Japan Times, Knowhere, MarketWatch, National Journal, New America, News24 (South Africa), New Zealand Herald, Pew Research, Politifact, Reuters, Texas Tribune, The Canadian Press, The Conversation, The Economist, Transparency International, Tribune News Service, Transpartisan Review, Washington Journal, WikiNews, World Economic Forum, World Politics Review and World Press Review.
I personally like to mix it up between: ABC News Australia, Associated Press, AFR, AFP, Euronews, Financial Times, Gallup, Investopedia, Pew, Reuters, The Conversation, The Economist, BBC, CNN, Mises Institute, France24, Bloomberg, Cato Institute, The Age and Herald Sun (Aus). So mostly neutral stuff with a bit of centre-left and centre-right sources.
I recommend the following resources to get a better idea:
https://mediabiasfactcheck.comhttps://www.snopes.com/