There are numerous ways to approach this situation. To begin, it's crucial to grasp the fundamentals of CSS Positioning, CSS Layout (Utilizing Grid / FlexBox / Float, etc.) & CSS BoxModel.
Based on the snippet you provided, I opted for float, although flex would have been my recommended choice due to its power and flexibility.
Here is the solution I devised.
/* EMPLOYING A MOBILE-FIRST APPROACH, DEFINING STYLES FOR MOBILE FIRST */
body {
padding: 0;
margin: 0;
font-family: sans-serif;
}
.image-stack {
position: relative;
}
.image-stack .bg {
position: absolute;
height: 100%;
width: 100%;
background: black;
}
.image-stack .bg>img {
opacity: .75;
width: 100%;
height: 100%;
object-fit: cover;
}
.image-stack .image-stack__item {
position: relative;
padding: 20px 10px;
height: 100%;
}
.col-half {
padding: 0 10px;
position: relative;
height: 100%;
}
.text-format {
color: white;
margin-bottom: 30px;
}
.text-format h1 {
font-size: 3rem;
font-weight: 700;
margin: 5px 0;
}
.img-overlap {
width: 100%;
height: 100%;
object-fit: cover;
}
@media screen and (min-width: 768px) {
.image-stack {
background: yellow;
height: 80vh;
margin-bottom: 60px;
}
.col-half {
width: calc(50% - 20px);
float: left;
}
.text-format {
margin-bottom: 0px;
}
.img-overlap {
position: absolute;
left: 0;
bottom: -30px;
}
}
<div class="image-stack">
<div class="bg">
<img src="https://picsum.photos/id/1045/1440/400">
</div>
<div class="image-stack__item">
<div class="col-half text-format">
<p>5th Consistent Award Winning Year!</p>
<h1>Modern Design Solutions</h1>
<p>A descriptive paragraph that tells clients how good you are and proves that you are the best choice.</p>
<p>A descriptive paragraph that tells clients how good you are and proves that you are the best choice.</p>
<a href="javascript:void(0)" class="btn">See our Projects</a>
</div>
<div class="col-half">
<img src="https://picsum.photos/id/1008/600/400" class="img-overlap" alt="Overlapping Image" />
</div>
<br clear="both" />
</div>
</div>
<div style="background: brown">
Other test
</div>
I included explanatory comments within the CSS section to assist you.
Explore the CodePen Link => https://jsfiddle.net/d5urpbL2/17/