1. The foreign pension is reported on
Schedule 1, 8 Other income. List type and amount, You type in "Foreign pension" $xx,xxx
Then transfer schedule 1 to 1040-SR, line 8.
2. You can use freefile program from IRS, https://www.irs.gov/filing/free-file-do-your-federal-taxes-for-free
Various tax reporting softwares participate in the program. I used Turbo Tax for my parents, it is free for federal income tax but not free for state tax returns, if applicable.