How big is your living room and how level is the current subfloor after removing the tiles?
Laying vinyl planks yourself is way easier than most people think - most folks can manage it without being a tradesperson. Here's the thing: it really depends on the subfloor. If you end up with a completely level floor after removing the tiles (and that's often the bigger job than the installation itself), it'll be pretty straightforward. You mainly just need patience when cutting around corners and a good utility knife. Most vinyl planks have click systems, so you don't even have to glue them - just click them together and you're done.
The real challenge is honestly the prep work. After removing the tiles you need to sand it clean and possibly apply self-leveling underlayment if there are any bumps. That's more annoying than actually laying the planks, but it's worth doing - otherwise your planks will look wavy later. Here's a handy tip: leave the planks lying around in the room for a day before gluing or installing them. The material needs time to adjust to the room's climate, otherwise you might run into expansion issues later. For larger areas it's probably worth getting a professional, since mistakes when cutting can get expensive fast - but for a standard-sized living room you really don't need outside help.