At the moment of this posting for a guide, Gears 5 Ranked is currently in Pre-Season.
However you are still able to manage to obtain this achievement.
There are 6 different ranks with 3 Tiers to each Rank.
Bronze 1, 2, 3 - Silver 1, 2, 3 - Gold 1, 2, 3, - etc...
We only need to get to Silver 1 which is the bright side and while playing in Bronze, you don't pay any GP to play in ranked, so it only comes down to a matter of how much time/games you need to play.
I unlocked this when I was playing King of the Hill Ranked.
For KotH, the point value system went as:
Bronze 1:
0 - 500
Bronze 2:
500 - 1250
Bronze 3:
1250 - 2000
That being said, overall you only need to accumulate 2000 GP overall.
500 for first tier, 750 for second tier and 750 again for third tier.
In King of the Hill, the point value system per game gets maxed out.
You will only obtain a max amount of 80 points for kills/eliminations, 10 points max for Ring Captures and 10 points max for Ring Breaks.
So for each game you can only obtain 100 GP for game play.
You will receive an additional 150 GP per win as well.
So with a win you can max out each game with 250 GP.
"Edit 8/27/2020: I have not checked myself in the ranked system, but Slipper21 has mentioned point system update."
Slipper21 says: Update for the new season. Bronze 2 requires 3000gp. Bronze 3 requires 7000gp (cumulative). A match win in KOTH rewards you with 1500gp. Silver 1 now requires 15000gp.
I am unsure how the point value system works in the other game modes, so please leave some notes if you take the other route and play those game modes instead.
Another point to make is when you do finally get to Silver Rank 1 and the achievement did not pop, simply reload the game so Gears 5 can adjust the stats properly. This happened to me as I was 155 GP into Silver 1. Simply quit and reloaded the game and the achievement popped.