They are generally around 3ft wide so it would fit, but having it so close to other units might not be a great idea. It'll be harder to access for maintenance and the other units may restrict airflow or cause it to heat up easier. Your best bet would be finding a spot that's got more room around it.

Twintech Heating & Cooling

https://twintechheating.ca/

They all have clearance requirements front and back, and sides.

It looks like the back up generator is not connected. See if it can be move 2-3 feet to the right. Another option is to raise the mini split condenser on a shelf above the other equipment. This would give more clearance and keep it away from snow drifts.

Yes, it is enough...But depend of the brand of your mini split. So, ask the size before purchase.

https://www.cooling-heating.org/