Geekoto Camera Tripod for DSLR, Compact 77" Aluminum Tripod with 360 Degree Ball Head and 8kgs Load for Travel and Work

Q: Can I use it to take both landscape and portrait shots? I often take both

Yes,sure. It's convenient to carry and long enough. You can take both landscape and portrait shots.

Q: Without handle how to you turn smoothly when shooting video?

It has fluid drift head, but it does not have a handle. I shot some video panning with it (see my review) and used the camera strap to pull the camera around smoothly. This was just my first attempt with panning on the camera, but it would be easy enough to rig a clamp and piece of rigging to the orange part of the head to make your own handle. If you have the gear already, this is a good free way to add a video arm.

Q: Has anyone used this as a rifle tripod?

I would recommend not using it for a rifle. I took this tripod with a normal size Leopold spotting scope with me to Somalia and used it on a 800 meter range. The spotting scope was at the upper limit of what the tripod could handle and if any wind came up it was unusable for anything beyond 200 meters. This is a tripod for a camera. I give it a C for use with a spotting scope (extended so that a 6 foot person could use it without having to kneel down). Shortening it to a kneeling position or lower would make it more stable.

Q: Is it sturdy enough for canon 5d mk iv with 70-200/2.8?

Yes it is. I put my Canon 6D with a 70-200. And with it in monopod mode too. I put my DJI Phantom 4 Pro controller on it with a tripod adapter too. No problems at all.