Ask HN: How to manage multiple interviews alongside a full-time job

I am based in Pakistan and currently working remotely full-time as a frontend developer. I want to move abroad, so from the past few months I have been actively started applying for companies in Germany in hopes to get hired.

I feel that interviewing is a very had process. First I have to put a lot of time to find an appropriate position, do research on the company and their culture and then apply for the position. After applying, I found the response rate to be very low. Around 5%-10% companies decide to start a screening call.

Next week, I have technical interviews with two German companies and I have to prepare for that alongside putting 8-10 hours everyday for my full-time job. I usually don't find the energy or will for interview preparation during weekdays and if an interview comes, I make sure it is scheduled in the next week so that I can prepare on weekends.

Those who have been through the same experience, how many jobs interviews do you think one should have in the pipeline at the same time so to not get overwhelmed?