Free video lessons of the Bulgarian language from the BNT TV channel are suitable for those who already understand speech well by ear and have some knowledge of grammar. The video course "I learn Bulgarian" was originally created with the aim of popularizing the Bulgarian language abroad, but its main goal is to help Bulgarian children and teenagers living outside of Bulgaria learn the Bulgarian language.
Test yourself: the first video has subtitles (in Bulgarian), you can turn subtitles on/off with one click on the square to the left of the gear icon. But don't rush to turn them on, listen to the dialogues first. Do you understand the meaning of what is said by ear? If you don't, can you transcribe the sounds you hear? If the speech rate is too fast for you, set the speed to 0.75 (click on the gear, then "playback speed").