it would certainly benefit you in veg most def. CO2 just speeds up the process, and the plant will also require more of it during really high temps - but i dont know what yours are.
BUT.. CO2 will only do well, if you kill your exhaust to the outside (if that applies), and do it while the lights are on. If you have good circulation then you dont need it per se. But extra will help move things along a bit quicker. Lots of info on this site abt this. But I can say that it is not a means to an end, or maybe better said, it will only work best if all your other elements are dialed in. Temp, water, nutes, lights, air, etc.
you can DIY.. just depends on your space, and doing some research i guess.. its best if you can get it releasing over the canopy of the plant(s). or a small space filled will do the trick. Tanks and generators are def more pro ways to go. I wouldnt waste my time with a Co2 Boost bucket. been there done that. pfft. Tanks are pricier than generators month to month, but arent as efficient in terms of output as a generator. But with a generator you have this propane flame going in your grow space. its a trade off
With a tank you will need a solenoid valve too. getting the tank is pricey, but refills are cheap. check like welding spots, or gas spots, places that do propane might have it if they are a specialty gas shop.
you dont want to go over 1500ppm in the space for CO2, that presents another issue of taking good precise measurements. Controllers are pricey. there are cheap methods from gro sto's but they arent as accurate.