Welcome! Whilst your question has already been answered, I felt compelled to throw my two pennies your way.
Burn scars can be a great place to practice. The trees are often compromised in multiple ways. It's dangerous, but can be excellent practice for dealing with hazard trees.
Second, I offer something of an admonition; Fell trees with three cuts only.
1.) GUNNING CUT. This cut is critical, it's how you aim the tree. DO NOT compromise your gun-cut.
2.) NOTCH. Humboldt or conventional, gapped face, etc. Block it out rather than compromise your gun.
3). BACK CUT. Do your best to keep it even, level. Bore cut trees prone to barberchair.
Gain control with a wedge, or other means, as soon as possible. Maintain control throughout the felling process.
Do not bother with fancy techniques until you have a solid grasp of these fundamentals. No sizwill, hanging Dutchman, shark gill, toggle, or other esoteric hootanannie.
Gun cut, face cut, back cut.
Stay safe, watch tops, not kerfs. Your neck SHOULD hurt after a day's work falling timber, else, you're not paying attention.
ALWAYS have wedgeS, and a way to drive them. You need more of them than you think you do.
Stay hydrated, add salts back in, LMNT, ReLyte, or other clean electrolyte supplements cannot be recommended enough. They help brain function among a host of other benefits. Hell, take a shaker of table salt with you, even that will help!
Swamp out with gusto! if it can reach you, if it can slow you down, it can kill you. Kill it first. Clean workspace, is happy workspace right?
I've probably missed a bunch. It's possible I've preached the gospel to a worthy acolyte. I only wish you to be safe and successful.