Hi Alexander,
For identifying these gaps, follow following steps
1. collect all papers which has discussed asynchronous intervention in learning due to COVID in past 2 years
2. Create a table of the tables having qualitative papers and separate the papers have quantitative aspect
3. Now see what all common things are there in each part. Highlight those and see what things are not yet explored.
This will help you in identifying your research gaps

Hi Acidri,
For including research knowledge and methodological gaps, follow these steps
1. Search all the recently published papers on the topic from reputed journals so as to identify the existing research knowledge
2. Compare the papers and understand what all areas has been explored.
3. List out the areas which could further could be explored.