The MacBook I recently got wants to hop to Tahoe

I got this old MacBook in almost perfect condition about 3 months ago. Runs nice with Linux Mint and Mavericks, but put OCLP to have it logged in with my Apple ID and HOLY cow this works very decently for a Core 2 duo!

I thought it will make me hop to the latest Big Sur but it wants to jump to Tahoe!