I think it almost impossible now, kase kelangan mo pc mag flash ng custom recovery, or mag unlock ng bootloader..but try mo dl magisk app, then dl mo ROM ng phone mo, kunin mo yung boot.img then pàtch mo yun manually gamit magisk
Suggest ko mg flash ka na lng ng custom rom na naka zip files may featured kasi yun na root user pedeng enabled/ disabled anytime memory card lng ok na khit walang pc pedeng mag flash. Sa stock rom kasi kahit mai- root mo kung hindi ka din elite root user limited lang ang access mo. Try mo ang crdroid custom rom