First thing that comes to mind is that sadly the Ranger does not get the Great weapon fighting style, a one-level dip into fighter will get you this, and you can take Defensive from Ranger for some ac goodness. This also gives you Con saves and Heavy armor, both very important things for a str user.
Anyways p.13 of the phb explains the point-buy system better than I can here so give it a read. As far as what to invest in, Con/Str/Wis in that order would be my recommendation. Being a front-line unit you will need all the survivability you can get and your hp is the first place to go for that, also Ensnaring strike/Hunter's mark are your best friends and they require concentration which means Con saves. After that str is your main source of damage so that is a priority. Then wisdom, this makes your spell save DC, you want it to be hard to get out of Ensnaring strike basically. I don't recall Duerger's Sub-race traits but I know they get a +2 to Con which will help you a Lot.
My recommendation for your stats
15 Str
8 Dex
15(17 racial) Con
8 Int
15 Wis
8 Cha
If the 8's scare you;
14 Str
10 Dex
14 (16) Con
10 Int
14 Wis
10 Cha
The main difference is that at your first ASI with the 8's you will be able to nab a 16 str and an 18 con at the same time, whereas with the 10's that will take you 2 ASI's.
As far as skills it is really up to you. I would advise Athletics and Perception. Shoving/grappling are athletics and Perception is always useful.
I hope that helped!
Super Bonus Alternate Build;
If you decide to go 1 in fighter you could also just go 3 in fighter and the rest Ranger. Picking Battle Master would give you a lot of cool options to help your pet attack too. Commander's strike can let him get a second swing in off-turn, Trip attack gives you both advantage, Distracting strike gives your pet advantage, and So-on.