I know nothing about hair extensions! Halp please!

I have read the sticky at the top of the page, but before buying anything I need to find out whether hair extensions are even what I want/need.

My hair is currently growing out from having two side shaves, it’s currently about an inch long on either side. I’ll try and attach a picture below. The rest of my hair is just about shoulder length.

My ideal end goal is this awesome fire hair - I’m hoping I can dye the rest of my hair red, maybe with orange tips and have extensions to both bulk out where I’ve flipped my hair to cover the side shave, and ombré into yellow at the bottom of the extensions.  I’ve removed darker colours before and had red a million times so the dye job isn’t a concern, just whether extensions will look ok or if they will be super obvious.

If extensions would work - I know nothing about extensions! Obviously clip-ins are cheaper and flexible, but would going to a hairdresser and getting “proper” extensions be better given my crazy hair cut? If so, what are the different options and price ranges? Are they uncomfortable to sleep on? What kind of maintenance do they require?

Any help massively appreciated!