Does a best practices guide for climbing safely exist online?
To learn safety you need a practical introduction by someone you're sure knows what they're talking about. Techniques can vary considerably between country and country and climbing techniques, e.g. it's common to use two half ropes in the UK. This is less common in other parts of the world. This leads to conflict (especially online) as what one country deems safe acceptable behaviour another country views as dangerous and sometimes bizarre. Sometimes this is for very good reason. Terrain and weather varies considerably, what is perfectly fine on a long straight bolted pitch in California may well be problematic on a meandering, wet, cold day, trad leading in the highlands of Scotland.
The nearest thing to a (international) standard on this kind of thing is the UIAA. A countries climbing federation (for example the BMC). Are accredited (or not) by the UIAA. This is an attempt to standardise the information internationally, see the mission statement:
The UIAA promotes the growth and protection of mountaineering and
climbing worldwide by:
- preserving their spirit and traditions
- advancing safe and ethical mountain practices
- promoting responsible access, culture and environmental protection
- supporting youth participation and the Olympic movement
So your best bet is to get in touch with your nearest UIAA accredited mountaineering federation and ask about safety courses. This will teach you the actual (not bad habits) proper safe way to do things.
Another option is a climbing club. Climbing clubs will be full of knowledgeable people who can teach you lots (not just safety). You're also going to have a better idea they know what they are doing. Just because someone says something forcefully does not make it correct. I've been told all sorts of odd things over the years, some of which are correct but a scary amount were plain wrong.