Beginners do well with two or three full-body sessions per week. As weekly volume grows, an upper/lower split across four days or a push/pull/legs rotation across three to six days both work well. The best split is the one that fits your actual schedule, because a programme you complete beats a theoretically superior one you abandon.
Each session covers a squat, a hinge, a push, a pull, and a carry. Every pattern gets practised two or three times a week, which is ideal while technique is still developing. This is the default recommendation for anyone in their first six to twelve months.
Two upper-body days and two lower-body days. Each muscle group still gets trained twice a week, but you have more time per session to add accessory work. This suits people who have outgrown full-body sessions and can commit to four fixed days.
Run three days a week, it gives each muscle one session; run six days, it gives two. It organises work neatly by pattern and is popular for building muscle. The six-day version demands real recovery capacity, so it is a poor first choice.
Count the days you can genuinely train, honestly, for the next three months. Two or three days points to full body. Four points to upper/lower. Five or six points to push/pull/legs or a specialised plan. Then hold that structure for at least eight to twelve weeks before judging it.
Athletes with sport practice should build the split around the sport, placing hard strength work away from key technical sessions rather than the other way round.