Oops! All woke!

graphics person here - so what you want to get is krita or gimp, krita has better UI, gimp is more versitile. Or photoshop if you feel like uhh, borrowing it from adobe (don't give them money they have enough)

• put them meme into the software or your choosing
• now if you can find a tool that says something like "healing" "spot healing" "patch" or "clone stamp" you can use them to remove the text that's already there, all those tools work a little differently but can get you where you want to be, so play around with them and find your favourite
• alternatively if that sounds too advanced you can brute force it, it won't look as seemless but it will get the job done. make a new layer, select a brush with soft edges and ~80% opacity, and then use the eyedropper tool (usual shortcut should be holding alt and clicking on the colour you want) and remove the text by covering it with the same colour that surrounds it. You'll notice how eventually the colour you sourced doesn't blend in, then what you need to do is grab a new colour that's nearby. Rinse and repeat until fully covered and blended
• add text
• if your text overlaps some parts of the image you don't want it to overlap you might find yourself wanting to erase a bit of it and not being able to. That's because the text is still text, fully editable. To change that you can either convert it to a normal layer (usually done by right clicking on the text layer and looking for something that says "convert") or (and that's the better option if you want to keep the text editable) you can apply a mask onto the text layer (should be a button for it next to "add layer" button), then as you have the mask selected draw with pure black over the elements you don't want the text to cover

i'm basing this mini-tutorial on photoshop so exact names and places of the tools you want might be different, but the process should be the same across most if not all image editing software

Unfortunately, I just share memes I find, I'm not the creator.