Start simple and work up.
Free float the bbl. Quick and easy to do yourself, and free if you have sandpaper.
Install steel or aluminum pillars and have a good bedding job done. If you are mechanically inclined you can do all this yourself for cheap.
Buy the best glass you can afford. Look at Vortex scopes if you never have. Incredible value, and several of them have lifetime no fault warranties . A couple other companies may have similar warranty, but don't know who.
Have someone do you a good trigger job or replace it. The new factory remington triggers suck.
That right there will get you off to a pretty good start unless you bought a dud.
Welcome to the addiction.