LBRY does not mess with your files or encode them for you so it is up to you to provide a useable format. In this video how i do it using the settings i use to get very busy music video's smaller (not saying its the only way, you could up the bitrate and resolution if you like and still be nice and steamable)
This video was encoded using the settings i showed, only difference is that my initial recording was not full screen so my resolution was different.
For bitrates here is some things i found checking what yt does: in most 720p 30fps video bitrates are around 2000/2500 for stuff that does not move much, if it does a bit more. I might go up to 4500 on my own very busy 720p 30fps music vids to keep a acceptable quality, but for stuff that does not move much Bitrates could be lower. Bitrates for 1080p are higher but do not need to be extremely high to achieve good results best to just try out what bitrates works for your type of material.
Some handy sites, a Resolution scale calculator here: https://bneijt.nl/pr/resolution-scale-calculator/ and a bitrate calcuator here https://www.dr-lex.be/info-stuff/videocalc.html