I need help with starting equipment

I would avoid any zoom lenses for astrophotography. For zoom lenses to work, certain optical sacrifices usually need to be made, and those will be compounded with astrophotography and all the POINT light sources (stars). Especially in the periphery of the frame. 

It is best to choose a prime lens for astrophotography. This need not necessarily be an expensive lens, some of the Samyang/Rokinon lenses deliver exceptional performance for astrophotography and are not too costly. A prime lens will help with ensuring quality stars throughout the field. NOT every lens, NOT every prime lens, is capable of producing good quality stars at the edges and particularly corners of the field. In fact, a majority will not. You should do your research and make sure whatever lens you choose is one that delivers good astrophotography performance, notably stars that are fairly round in the corners, rather than comet shaped, cross shaped, or otherwise abberated. There are a lot fewer lenses that can do that, than lenses that can deliver good quality terrestrial (i.e. landscapes, wildlife, portraiture, still life, etc.) performance. 

As Guillermo shared, focus is going to be a challenge. Most optical systems need regular re-focusing throughout the night to maintain good enough focus for astrophotography. For that, you may want to look into a more expensive lens than a Samyang/Rokinon and look into a Canon prime lens with autofocus capabilities. If you have a Canon DSLR with a Canon AF lens, then you could use software such as APT or BackyardEOS to help you focus. With APT if can be automated, which can be helpful (well…the docs say so, now that I think about it I am not sure if it works with a DSLR; worth trying though) in quickly maintaining focus throughout the night. BackyardEOS doesn't support autofocus, but it does have focusing capabilities that make it pretty easy to find optimal focus fairly quickly. The way I used to do it was to set up a short sequence, let it rip, then focus after it was done, and repeat as desired. 

Exactly what lens would depend on what you want to image. FWIW, imaging smaller objects with greater magnification is harder to do, even with a prime lens. Wider fields are easier, although ultra wide fields will usually present their own issues. Medium to wideish fields are probably the sweet spot for a beginner. I would say a 24mm, 50mm, 100mm or 200mm lens would do the trick, let you get started, without presenting too much of a tracking challenge. A StarAdventurer is a good little mount. I have one, and it seems the major change with the 2i is wifi maybe? I don't know what else may have changed, but mine has been a pretty reliable little mount. Its not the best available, but its good for a start. There used to be an alternative called the Fornax LighTrack II, which I thought was a better quality, better designed mount. That said, I cannot reach their web site, so I don't know if they are still in business. 

Good tracking, good focus…I think these two things are key. That, and corner star performance (when focused) in your lens.

Many people here will tell you not to get the 75-300mm kit lens, many of whom I suspect have never owned or even tried one.  I learned the hard way that throwing money at this hobby is not the way to learn it.  Fancy equipment comes with a learning curve, it doesn't automagically make your pictures better or easier to capture.

I suggest you watch youtube videos from well known astrophotographers who tested this lens and decide for yourself.  You'll be surprised.   Here's a few, I am sure a quick search would lead to many more.

Astrobackyard: 
https://youtu.be/_gllwIvPqGE?si=K_z-0GHmxxx3bqf7

Astrobackyard and Nebula Photos (they had little competition): 
https://youtu.be/_gllwIvPqGE?si=K_z-0GHmxxx3bqf7
https://youtu.be/ITe0VI02t-8?si=rrDnGkP6_MgMh46F

Delta astrophotography: 
https://youtu.be/4r8tib5QQ90?si=X8qouh8kUghBlo3N
https://youtu.be/CmzpCugYF1A?si=dlCSK0iOp2Bh5sy4