Along with a book (lots of good recommendations to choose from here), I recommend getting yourself some basic tools for practical experimentation: breadboard, multimeter (even a cheap Chinesium model will be fine for low voltage DC work), an oscilloscope (entry level DSO models from Chinese OEMs such as Siglent and Rigol can be had very affordably), a bench power supply (Siglent and Rigol also offer these), and some components (Joe Knows kits that are sold on Amazon are a great way to stock up on decent quality resistors, capacitors, and semiconductors to help you get to building circuits).
If you get to wanting to experiment with faster circuits, you can ditch breadboards and their parasitics for Manhattan style construction[1] and be able to build _much_ faster circuits with better success. Or you can fall down another rabbit hole, learning how to design your own PCBs. With PCB services becoming mainstream nowadays, you can learn a tool such as KiCad (free software) and send out your gerbers to be manufactured for cheap.
If you get to wanting to experiment with faster circuits, you can ditch breadboards and their parasitics for Manhattan style construction[1] and be able to build _much_ faster circuits with better success. Or you can fall down another rabbit hole, learning how to design your own PCBs. With PCB services becoming mainstream nowadays, you can learn a tool such as KiCad (free software) and send out your gerbers to be manufactured for cheap.
[1]: http://www.sdmakersguild.org/the-art-of-manhattan-style-circ...