The full suite of Adobe products is available form Adobe. The latest versions of many of their products may support Apple-silicon M1 processor natively, and all others work through Rosetta emulation (which is automatically invoked when needed).
Preview is already installed on your Mac, and can be used to read existing pdf documents.
Apple provides Pages software, a cross between word-processor and lightweight page-layout, free, already installed on most Macs. It can, if you ask it to, both read and write Microsoft Word format files.
Numbers is free and available for spreadsheets. (if you ask it to, both read and write Microsoft Excel format files.)
Keynote is free and available for Presentations. (if you ask it to, both read and write Microsoft PowerPoint format files.)
There are also several Office 'work-alike' packages available as Open Software. LibreOffice and OpenOffice and NeoOffice come to mind.
You can also one-time purchase or procure an Office 365 subscription direct from Microsoft.