Learning an instrument is always a challenging task, so you want to make it as easy as possible for yourself! With the guitar, it can be a bit of an uphill battle, so it’s best to go in well prepared.
In many cases, the traditional steel-string Acoustic guitar can be the hardest to play. The strings tend to have a heavier gauge which makes things harder when first learning.
The metal strings also means that your fingers will ache after playing while new to the instrument. Eventually, callouses will form which removes this, but it can be off-putting at first.
If you can get over the discomfort as your fingers toughen up, then the acoustic is a great avenue to go down when learning, but it can dissuade many new players.
Electric guitars tend to use fairly light strings compared to their acoustic counterparts. This means that they are a bit easier to play. With lead guitar playing popularising the use of bends and faster playing, having lighter strings makes this much easier.
The problem with electric guitars are that they generally also require an amp, bringing the price up quite a bit.
When you’re a younger learner, occasionally school teachers will favour acoustic instruments rather than electric ones. I would suggest starting on an electric guitar more if that is the route you would like to go down, even though the skills are transferable to acoustic instruments.
The easiest guitars to learn on, in my opinion, are classical guitars. They use nylon strings which are much easier on the fingers as they have less tension. This means you don’t have the barrier of building callouses to worry about, you can just focus on learning.
The downfall of classical guitars is that they aren’t used as often in modern music. So, they don’t sound as close to what you would hear on the radio as other types.
However, they are perfect for all ages. Readily coming in smaller sizes, as well as full size, they make great starter instruments.