In terms of that fit taking on Dagan alone: It will do it - basically you need to do more than 100dps to break his repair rate - that fit is going to be something above 150dps at about 1km. Check in the fitting window.
Teaming up with others to kill Dagan is a good approach. Ask in local, there are friendly people there. If you are struggling reach out in game to me - if I’m online I’ll come and help.
In terms of the fit there are some obvious upgrades:
Use Limited Light Neutron Blaster I rather than the very basic weapon you have - that’s good for another 10% damage, a bit more range and a bit less CPU to fit them (yes, they are 150k ISK each, compared to 60k ISK, but it’s worth it!) - The best non-T2 neutron blasters are the Modals, but they are 2m each and if you are new you may flinch at that. You’ll rapidly get to a point where that feels like a good investment though.
Skills really, really help. Each level trained on Small Hybrid Turret is another 5% of damage from any small hybrids you fit. Level IV is a sweet spot of time/benefit for a new player. Likewise, training Gallente Destroyer gives a tracking and range bonus to the weapons - that’s useful as it means you will hit more reliably and at a better range. The usual Gunnery Skills all add up in the mix as well: Rapid Fire, Surgical Strike, Gunnery - all have bonuses to damage or rate of fire that help appreciably. Check out the rest of the skills - range and tracking improvements are always nice.
Ultimately: give it a try - it may be a struggle, or may be easy for you - but you won’t know 'til you try it. And if it’s a struggle but you over come him - you’ll have the satisfaction of learning what you can really achieve in Eve.