This will add meta data to the member profile in Memberstack which allows us to hide or show the mark as complete form.

No Code Membership Demo Mark As Complete

<script src="https://api.memberstack.io/static/memberstack.js?webflow" data-memberstack-id="GET_FROM_MEMBERSTACK"></script>

<script>
MemberStack.onReady.then(async function(member) {

	// Checks if member is logged in
	if(member.loggedIn){
		const metadata = await member.getMetaData();

	// If no metadata.liked_topics exists, create it in MemberStack.
		metadata.liked_topics = metadata.liked_topics || [];

	// If no metadata.completed_topics exists, create it in MemberStack.
		metadata.completed_topics = metadata.completed_topics || [];

	// Defines the webflow ID to a const of itemID (Pull this from the CMS)
		const itemID = "GET_FROM_CMS";

	// If they have the item ID in their profile, hide the form, show the appropriate button
		if(metadata.liked_topics.includes(itemID)){
			document.getElementById('like-topic').style.display = 'none';
			document.getElementById('unlike-topic').style.display = 'block';
		};
		
        	if(metadata.completed_topics.includes(itemID)){
			document.getElementById('complete-topic').style.display = 'none';
			document.getElementById('uncomplete-topic').style.display = 'block';
		};
		
	// When the like-topic button is clicked, if the itemID doesn't exist on their profile
	// add it, then push the metadata to MemberStack.
		$('#like-topic').click(function(){
			if(metadata.liked_topics.indexOf(itemID) === -1){
				metadata.liked_topics.push(itemID);
				member.updateMetaData(metadata);
				setTimeout(function(){ location.reload(); }, 3000);
			}
		});
	
	// When the complete-topic button is clicked, if the itemID doesn't exist on their profile
	// add it, then push the metadata to MemberStack.
		$('#complete-topic').click(function(){
			if(metadata.completed_topics.indexOf(itemID) === -1){
				metadata.completed_topics.push(itemID);
				member.updateMetaData(metadata);
				setTimeout(function(){ location.reload(); }, 3000);
			}
		});	
    
	// When the unlike-topic button is clicked, if the itemID exists on their profile
	// remove it, then push the metadata to MemberStack.
		$('#unlike-topic').click(function(){
			if(metadata.liked_topics.includes(itemID)){
				const itemIndex = metadata.liked_topics.indexOf(itemID);
				metadata.liked_topics.splice(itemIndex);
				member.updateMetaData(metadata);
				setTimeout(function(){ location.reload(); }, 3000);
			}
		});
        
	// When the uncomplete-topic button is clicked, if the itemID exists on their profile
	// remove it, then push the metadata to MemberStack.
		$('#uncomplete-topic').click(function(){
			if(metadata.completed_topics.includes(itemID)){
				const itemIndex = metadata.completed_topics.indexOf(itemID);
				metadata.completed_topics.splice(itemIndex);
				member.updateMetaData(metadata);
				setTimeout(function(){ location.reload(); }, 3000);
			}
		});
	}
});
</script>

Setting up to add and remove items from metadata.