Wikipedia is free for everyone to edit. The policies are strongly aligned with the pursuit of truth. Both parties can have truths in their favour, if editors are in a left wing bubble they may just be more exposed to truths from a left perspective. Here's where you can help! If you identify bias, feel free to remove charged language, and add new ideas with reliable citations. Here's a list of sources considered reliable: https://en.wikipedia.org/wiki/Wikipedia%3AReliable_sources%2...

Extensive discussions of the decision making process for each source is documented in this list.

Well, I try, but I’m never allowed to edit anything, even though I add sources, so no idea what’s happening there.

There's always Conservapedia if Wikipedia isn't working for you!