How to make transitioning into new jobs easier ?

Hello, How do you handle the process of transitioning into new jobs? I am a software engineer who works remotely, and it has been almost three months since I started my new job. I am currently working with a legacy code base, which presents its challenges. Initially, I received only one hour of knowledge transfer from my tech lead, two weeks into my job, and now they expect me to work on tasks as if I have been with the company for a long time. I don't expect to be spoon-fed everything, but I do hope for some assistance in understanding the functionality and the overall process. While we can always search the internet for technical queries, for matters related to the process and other specific aspects, we rely on our teammates. Unfortunately, they haven't been very helpful either. Another issue is the communication gap since most of my team is located across Europe. Could you please provide some suggestions on how I can make this transition smoother? TIA.