I've recently started learning how to play guitar and recently bough my first guitar, a Jim Root Signature Squire Telecaster (I love it!). I have a small portion of my budget left and was wondering whether to buy a new amp (using a park by marshall 15 watt amp at the moment) or to buy a Fender CD-60 acoustic. What would your advice be? Does a beginner need a acoustic and a electric? Would it be bad to learn to play on the both or would that be better?
The funny thing is, you'll likely receive several answers to your question, and none of them are wrong.

First of all, congrats on deciding to learn to play the guitar. If you stick with it, it will reward you the rest of your life and can lead to many cool things, such as learning other instruments, teaching guitar, playing with others, etc...

So, should you buy a new amp, or a new acoustic? You haven't really specified what your budget is, but the answer is going to depend on where you see yourself heading. The experts will tell you different things. Some will say you need to learn on an acoustic, while others will say you need to learn on an electric. I can tell you that there is a greater chance of a new player getting discouraged and quitting, if they start with an acoustic. The strings require a lot more pressure to fret. When they realize their finger strength is not up to the task, some will push through it and some will quit. If you start with an electric, the strings are quite a bit lighter and are easier to fret, which gives you a fighting chance.

So, back to my original question? Where do you see yourself in a few years? Mostly playing acoustic or electric? How's your finger strength? When I started out, I bought an electric. A couple of years later I bought a nice acoustic, but couldn't play barre chords on it for more than a few minutes. As a result, it stayed up on the wall most of the time. Shortly after that, I decided that it was time to conquer the acoustic, so I started picking it up more and more, working on the barre chords and increasing my finger strength. Somewhere during that time, I decided that I preferred playing acoustic. Now, about the only time I play an electric is when I'm playing lead with the group I'm in. I would recommend that you visit your local guitar stores and play some good quality acoustic guitars. I'm not saying the Fender CD-60 is a cheap acoustic, but there are certainly better ones available. If you decide to get one later, you can always save up and buy a nice one in a couple of years.

If you're going to buy a better amp, it needs to be a significant improvement. The amp you have now is regarded as a practice, or bedroom amp. Don't buy another practice amp, as it won't be an upgrade and you'll still need to upgrade to something better, should you decide to gig later on.
I'm going to start by agreeing with KG6_Steven, you may get discouraged if you stick just with acoustic. But in your case, I feel getting an acoustic would be a lot smarter as you would have both electric and acoustic. Your current amp is perfect for starting out, upgrading can be saved for later. When I started I had both an acoustic and electric available to me so I played the shite out of both. Playing acoustic helped me build hand strength, chord progression, and especially build callus. I often learn songs on acoustic to memorize them and then switching to electric makes playing them a lot easier in comparison.

All I'm saying is that the acoustic guitar is the much better alternative; having both will only help you (especially if you also enjoy acoustic music too) and every guitarist has one in their arsenal.

Good luck with learning and don't give up
Thanks for the replies guys I'm a massive metal/grunge fan as you can tell by the profile picture and my choice of guitar haha. But, I do like Nirvana and Slipknot's unplugged and stuff, so having a acoustic would be really fun to learn that stuff. I only have a £100, so a CD-60 is probably the best I can get for that money and it would help me build finger strength and would give some nice variety and I could play when I travel. As for the future, I do see myself as a lead electric guitarist, but i'd still enjoy playing acoustic a lot.